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2016(the)X
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3809(inode.)X
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582(e.g.)X
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726(fsck)X
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864(\(8\)\),)X
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3992(groups)X
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691(leaving)X
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842(second)X
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10 f
555 5541(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)N
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1 f
727 5619(1)N
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763 5644(To)N
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1195(Proceedings)X
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2201(,)X
2233(San)X
2345(Francisco,)X
2625(CA,)X
2746(January)X
2960(1992.)X
2 p
8 s 8 xH 0 xS 1 f
10 s
3 f
1 f
555 630(have)N
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2540(nm)X
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555 1203(ing)N
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3 f
555 1749(2.)N
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1 f
755 1872(There)N
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555 1962 0.1172([SPEC88][NODI90][CHEN91][MOHA91].)AN
2009(Much)X
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555 2715(then)N
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555 2805(buffer)N
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2002(fsync)X
1 f
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555 3288(opposed)N
846(to)X
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755 3591(Finally,)N
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10 f
863 4393(i)N
870(iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii)X
1 f
903 4483(Buffer)N
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10 f
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870(iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii)X
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3109(4K)X
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1672 5033(g)N
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1985(organization)X
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2646(is)X
2719(redundantly)X
3122(expressed.)X
10 f
863 5043(i)N
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1 f
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2323(deadlocks,)X
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3373(locking)X
3638(\(2PL\).)X
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3708(coupled)X
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3996([BAY77])X
555 1782(during)N
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1724(coupled)X
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2011(during)X
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2231(the)X
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555 2838(user)N
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744(early.)X
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555 3534([BAY77],)N
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3 f
555 3990(3.1.3.)N
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555 4749(3.2.)N
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3629(db)X
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10 s 10 xH 0 xS 1 f
3 f
1 f
11 s
1851 1520(log_commit)N
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17 s
1163 960(Txn)N
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2363 726 MXY
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1116 MX
0 535 Dl
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726 MY
0 355 Dl
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1 f
11 s
2207 1297(lock)N
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2319 2508 MXY
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4 23 Dl
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36 -7 Dl
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3277 2455(sleep_on)N
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36 4 Dl
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1 -22 Dl
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1070 -535 Dl
2631 2508 MXY
36 6 Dl
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3 -22 Dl
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891 -357 Dl
1426 2455(sleep_on)N
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11 20 Dl
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1554 2366(wake)N
3277(wake)X
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3 f
17 s
1236 1851(Lock)N
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1950 2654(Process)N
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1 f
11 s
2207 1364(unlock)N
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20 -31 Dl
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19 31 Dl
0 -357 Dl
2497 2322(sleep_on)N
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-1 Ds
3 f
10 s
1790 2830(Figure)N
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10 f
555 3010(h)N
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907(Log)X
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905(log_commit)X
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1920(exactly)X
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2322(the)X
2 f
2445(log)X
1 f
2572(operation)X
2900(but)X
3026(guarantees)X
3394(that)X
3538(the)X
3660(log)X
3786(has)X
3917(been)X
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555 4252(to)N
643(disk)X
802(before)X
1034(returning.)X
1394(A)X
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1837(of)X
1930(our)X
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2333(strategy)X
2613(appears)X
2884(in)X
2971(the)X
3094(implementation)X
3621(section)X
3873(\(section)X
4152(4.2\).)X
2 f
555 4342(Log_unroll)N
1 f
935(reads)X
1126(log)X
1249(records)X
1507(from)X
1684(the)X
1803(log,)X
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2611(transaction)X
2983(pointers)X
3261(and)X
3397(calling)X
3635(the)X
3753(appropriate)X
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555 4432(routines)N
839(to)X
927(implement)X
1295(transaction)X
1673(abort.)X
1904(In)X
1997(a)X
2059(similar)X
2307(manner,)X
2 f
2594(log_roll)X
1 f
2877(reads)X
3073(log)X
3201(records)X
3464(sequentially)X
3877(forward,)X
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555 4522(ling)N
699(the)X
817(appropriate)X
1203(redo)X
1366(routines)X
1644(to)X
1726(recover)X
1988(committed)X
2350(transactions)X
2753(after)X
2921(a)X
2977(system)X
3219(crash.)X
3 f
555 4708(3.2.2.)N
775(The)X
928(Buffer)X
1171(Manager)X
1 f
755 4831(The)N
3 f
912(Buffer)X
1167(Manager)X
1 f
1511(uses)X
1681(a)X
1749(pool)X
1923(of)X
2022(shared)X
2264(memory)X
2563(to)X
2657(provide)X
2934(a)X
3002(least-recently-used)X
3641(\(LRU\))X
3886(block)X
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555 4921(Although)N
886(the)X
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1818(an)X
1923(LRU)X
2112(cache,)X
2345(it)X
2418(would)X
2647(be)X
2752(simple)X
2994(to)X
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3534(replacement)X
3955(policies)X
4232(as)X
555 5011(suggested)N
903(by)X
1015([CHOU85])X
1408(or)X
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1601(provide)X
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2405(pools)X
2610(with)X
2784(different)X
3092(policies.)X
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4116(pages)X
555 5101(from)N
736(the)X
859(buffer)X
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3 f
1886(pinned)X
1 f
2145(to)X
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2466(that)X
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3021(written)X
3272(to)X
3358(disk)X
3515(while)X
3717(they)X
3879(are)X
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4088(a)X
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555 5191(cally)N
732(inconsistent)X
1135(state.)X
1343(When)X
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1729(replacement)X
2143(is)X
2217(necessary,)X
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3 f
2689(Buffer)X
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1 f
3264(\256nds)X
3439(an)X
3535(unpinned)X
3853(page)X
4025(and)X
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555 5281(checks)N
794(with)X
956(the)X
3 f
1074(Log)X
1227(Manager)X
1 f
1559(to)X
1641(ensure)X
1871(that)X
2011(the)X
2129(write-ahead)X
2529(protocol)X
2816(is)X
2889(enforced.)X
3 f
555 5467(3.2.3.)N
775(The)X
928(Lock)X
1121(Manager)X
1 f
755 5590(The)N
3 f
901(Lock)X
1095(Manager)X
1 f
1428(supports)X
1720(general)X
1978(purpose)X
2253(locking)X
2514(\(single)X
2753(writer,)X
2986(multiple)X
3273(readers\))X
3553(which)X
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3842(currently)X
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555 5680(to)N
638(provide)X
904(two-phase)X
1254(locking)X
1514(and)X
1650(high)X
1812(concurrency)X
2230(B-tree)X
2451(locking.)X
2751(However,)X
3086(the)X
3204(general)X
3461(purpose)X
3735(nature)X
3956(of)X
4043(the)X
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6 p
10 s 10 xH 0 xS 1 f
3 f
1 f
555 630(manager)N
857(provides)X
1158(the)X
1281(ability)X
1510(to)X
1597(support)X
1862(a)X
1923(variety)X
2171(of)X
2263(locking)X
2528(protocols.)X
2890(Currently,)X
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3345(locks)X
3538(are)X
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3967(the)X
4089(granu-)X
555 720(larity)N
747(of)X
837(a)X
896(page)X
1071(\(the)X
1219(size)X
1367(of)X
1457(a)X
1516(buffer)X
1736(in)X
1821(the)X
1942(buffer)X
2161(pool\))X
2352(which)X
2570(is)X
2645(identi\256ed)X
2969(by)X
3071(two)X
3213(4-byte)X
3440(integers)X
3716(\(a)X
3801(\256le)X
3925(id)X
4009(and)X
4147(page)X
555 810(number\).)N
898(This)X
1071(provides)X
1378(the)X
1507(necessary)X
1851(information)X
2259(to)X
2351(extend)X
2595(the)X
3 f
2723(Lock)X
2926(Manager)X
1 f
3268(to)X
3360(perform)X
3649(hierarchical)X
4059(locking)X
555 900([GRAY76].)N
982(The)X
1133(current)X
1387(implementation)X
1915(does)X
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2216(support)X
2482(locks)X
2677(at)X
2760(other)X
2950(granularities)X
3376(and)X
3517(does)X
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3816(promote)X
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555 990(these)N
740(are)X
859(obvious)X
1132(future)X
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1657(to)X
1739(the)X
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755 1113(If)N
831(an)X
929(incoming)X
1253(lock)X
1413(request)X
1667(cannot)X
1903(be)X
2001(granted,)X
2284(the)X
2404(requesting)X
2760(process)X
3023(is)X
3098(queued)X
3352(for)X
3467(the)X
3586(lock)X
3745(and)X
3882(descheduled.)X
555 1203(When)N
769(a)X
827(lock)X
987(is)X
1062(released,)X
1368(the)X
1488(wait)X
1647(queue)X
1860(is)X
1934(traversed)X
2250(and)X
2387(any)X
2524(newly)X
2741(compatible)X
3118(locks)X
3308(are)X
3428(granted.)X
3730(Locks)X
3947(are)X
4067(located)X
555 1293(via)N
680(a)X
743(\256le)X
872(and)X
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1551(and)X
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1820(chained)X
2097(both)X
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2373(object)X
2595(and)X
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2843(transaction,)X
3241(facilitating)X
3614(rapid)X
3805(traversal)X
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4201(the)X
555 1383(lock)N
713(table)X
889(during)X
1118(transaction)X
1490(commit)X
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1890(abort.)X
755 1506(The)N
907(primary)X
1188(interfaces)X
1528(to)X
1617(the)X
1742(lock)X
1907(manager)X
2211(are)X
2 f
2337(lock)X
1 f
2471(,)X
2 f
2518(unlock)X
1 f
2732(,)X
2779(and)X
2 f
2922(lock_unlock_all)X
1 f
3434(.)X
2 f
3500(Lock)X
1 f
3682(obtains)X
3939(a)X
4001(new)X
4161(lock)X
555 1596(for)N
680(a)X
747(speci\256c)X
1023(object.)X
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1638(also)X
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1947(variants)X
2231(of)X
2328(the)X
2 f
2456(lock)X
1 f
2620(request,)X
2 f
2902(lock_upgrade)X
1 f
3373(and)X
2 f
3519(lock_downgrade)X
1 f
4053(,)X
4103(which)X
555 1686(allow)N
755(the)X
875(caller)X
1076(to)X
1160(atomically)X
1519(trade)X
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2005(one)X
2142(type)X
2301(for)X
2416(a)X
2473(lock)X
2632(of)X
2720(another.)X
2 f
3022(Unlock)X
1 f
3275(releases)X
3551(a)X
3608(speci\256c)X
3874(mode)X
4073(of)X
4161(lock)X
555 1776(on)N
655(a)X
711(speci\256c)X
976(object.)X
2 f
1232(Lock_unlock_all)X
1 f
1786(releases)X
2061(all)X
2161(the)X
2279(locks)X
2468(associated)X
2818(with)X
2980(a)X
3036(speci\256c)X
3301(transaction.)X
3 f
555 1962(3.2.4.)N
775(The)X
928(Process)X
1207(Manager)X
1 f
755 2085(The)N
3 f
900(Process)X
1179(Manager)X
1 f
1511(acts)X
1656(as)X
1743(a)X
1799(user-level)X
2136(scheduler)X
2464(to)X
2546(make)X
2740(processes)X
3068(wait)X
3226(on)X
3326(unavailable)X
3716(locks)X
3905(and)X
4041(pending)X
555 2175(buffer)N
778(cache)X
988(I/O.)X
1161(For)X
1297(each)X
1470(process,)X
1756(a)X
1817(semaphore)X
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2268(maintained)X
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3055(that)X
3200(process)X
3466(waits)X
3660(when)X
3859(it)X
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1014(When)X
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2549(is)X
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555 2445(process)N
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3775(to)X
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555 2535(ef\256ciently)N
900(with)X
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2462(compromised)X
2918(our)X
3045(commitment)X
3469(to)X
3551(a)X
3607(user-level)X
3944(package.)X
3 f
555 2721(3.2.5.)N
775(The)X
928(Transaction)X
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1 f
755 2844(The)N
3 f
901(Transaction)X
1335(Manager)X
1 f
1668(provides)X
1965(the)X
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2 f
2768(txn_begin)X
1 f
3084(,)X
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3125(txn_commit)X
1 f
3499(,)X
3540(and)X
2 f
3676(txn_abort)X
1 f
3987(.)X
4047(It)X
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742(of)X
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2467(identi\256ers,)X
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555 3024(When)N
772(a)X
2 f
833(txn_begin)X
1 f
1174(is)X
1252(issued,)X
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3 f
1620(Transaction)X
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1 f
2395(assigns)X
2651(the)X
2773(next)X
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3249(transaction)X
3625(identi\256er,)X
3958(allocates)X
4263(a)X
555 3114(per-process)N
948(transaction)X
1322(structure)X
1625(in)X
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3028(active)X
3241(transactions,)X
3665(and)X
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555 3204(transaction)N
937(identi\256er)X
1256(to)X
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2573(transaction)X
2954(structure)X
3264(contains)X
3560(a)X
3625(pointer)X
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555 3294(table)N
734(for)X
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3430(\()X
2 f
3457(idle)X
1 f
(,)S
2 f
3620(running)X
1 f
3873(,)X
2 f
3915(aborting)X
1 f
4190(,)X
4232(or)X
2 f
555 3384(committing\))N
1 f
942(,)X
982(an)X
1078(error)X
1255(code,)X
1447(and)X
1583(a)X
1639(semaphore)X
2007(identi\256er.)X
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859(commit,)X
1147(the)X
3 f
1269(Transaction)X
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2042(calls)X
2 f
2213(log_commit)X
1 f
2615(to)X
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743(it)X
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1168(Lock)X
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1699(to)X
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4083(aborts,)X
555 3687(the)N
3 f
680(Transaction)X
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1 f
1459(calls)X
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2 f
1739(log_unroll)X
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2102(to)X
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3043(records)X
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555 3777(the)N
673(database.)X
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2 f
2151(lock_unlock_all)X
1 f
2683(to)X
2765(release)X
3009(the)X
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3557(locks.)X
3 f
555 3963(3.2.6.)N
775(The)X
928(Record)X
1198(Manager)X
1 f
755 4086(The)N
3 f
919(Record)X
1208(Manager)X
1 f
1559(supports)X
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3484(to)X
3585(a)X
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555 4176(modi\256ed)N
861(the)X
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1101(database)X
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3 f
1905(db)X
1 f
1993(\(3\))X
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2418(to)X
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3079(and)X
3216(buffer)X
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3803(In)X
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1849(redo,)X
2037(the)X
3 f
2160(Record)X
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1 f
2770(de\256nes)X
3021(a)X
3081(collection)X
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1444(routines.)X
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3 f
1937(Log)X
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1 f
2452(performs)X
2777(a)X
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951(routines.)X
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3428(types:)X
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808(operation)X
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2402(an)X
2498(insert)X
2696(and)X
2832(is)X
2905(logged)X
3143(accordingly.)X
3 f
555 4722(3.3.)N
715(Application)X
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1 f
755 4845(The)N
907(structure)X
1215(of)X
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1558(allows)X
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2507(to)X
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3339(and)X
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4138(large)X
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810(of)X
901(LIBTP's)X
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2468(structures)X
2804(in)X
2889(shared)X
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3432(its)X
3530(structures)X
3865(are)X
3987(subject)X
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926(by)X
1043(applications)X
1467(when)X
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2673(with)X
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3420(For)X
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3720(reason,)X
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555 5115(designed)N
864(to)X
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1558(into)X
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2537(which)X
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3016(accessed)X
3321(via)X
3442(a)X
3501(socket)X
3729(interface.)X
4094(In)X
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555 5205(way)N
712(LIBTP's)X
1015(data)X
1172(structures)X
1507(are)X
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1951(from)X
2130(application)X
2509(code,)X
2704(but)X
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3349(overhead)X
3666(is)X
3741(increased.)X
4107(When)X
555 5295(applications)N
975(are)X
1107(trusted,)X
1377(LIBTP)X
1631(may)X
1801(be)X
1909(compiled)X
2239(directly)X
2516(into)X
2672(the)X
2802(application)X
3190(providing)X
3533(improved)X
3872(performance.)X
555 5385(Figures)N
815(two)X
955(and)X
1091(three)X
1272(show)X
1461(the)X
1579(two)X
1719(alternate)X
2016(application)X
2392(architectures.)X
755 5508(There)N
964(are)X
1084(potentially)X
1447(two)X
1588(modes)X
1818(in)X
1901(which)X
2118(one)X
2255(might)X
2462(use)X
2590(LIBTP)X
2833(in)X
2916(a)X
2972(server)X
3189(based)X
3392(architecture.)X
3832(In)X
3919(the)X
4037(\256rst,)X
4201(the)X
555 5598(server)N
778(would)X
1004(provide)X
1275(the)X
1399(capability)X
1741(to)X
1829(respond)X
2109(to)X
2197(requests)X
2486(to)X
2574(each)X
2747(of)X
2839(the)X
2962(low)X
3107(level)X
3288(modules)X
3584(\(lock,)X
3794(log,)X
3941(buffer,)X
4183(and)X
555 5688(transaction)N
944(managers\).)X
1356(Unfortunately,)X
1863(the)X
1998(performance)X
2442(of)X
2546(such)X
2730(a)X
2803(system)X
3062(is)X
3152(likely)X
3371(to)X
3470(be)X
3583(blindingly)X
3947(slow)X
4134(since)X
7 p
10 s 10 xH 0 xS 1 f
3 f
1 f
1 Dt
1864 1125 MXY
15 -26 Dl
-15 10 Dl
-14 -10 Dl
14 26 Dl
0 -266 Dl
1315 1125 MXY
15 -26 Dl
-15 10 Dl
-14 -10 Dl
14 26 Dl
0 -266 Dl
3 Dt
1133 1125 MXY
0 798 Dl
931 0 Dl
0 -798 Dl
-931 0 Dl
1 Dt
1266 1257 MXY
0 133 Dl
665 0 Dl
0 -133 Dl
-665 0 Dl
3 f
8 s
1513 1351(driver)N
1502 1617(LIBTP)N
1266 1390 MXY
0 400 Dl
665 0 Dl
0 -400 Dl
-665 0 Dl
3 Dt
1133 726 MXY
0 133 Dl
931 0 Dl
0 -133 Dl
-931 0 Dl
1 f
1029 1098(txn_abort)N
964 1015(txn_commit)N
1018 932(txn_begin)N
1910 1015(db_ops)N
3 f
1308 820(Application)N
1645(Program)X
1398 1218(Server)N
1594(Process)X
1 f
1390 986(socket)N
1569(interface)X
1 Dt
1848 967 MXY
-23 -14 Dl
8 14 Dl
-8 15 Dl
23 -15 Dl
-50 0 Dl
1324 MX
23 15 Dl
-9 -15 Dl
9 -14 Dl
-23 14 Dl
50 0 Dl
3 Dt
2862 859 MXY
0 1064 Dl
932 0 Dl
0 -1064 Dl
-932 0 Dl
1 Dt
3178 1390 MXY
24 -12 Dl
-17 0 Dl
-8 -15 Dl
1 27 Dl
150 -265 Dl
3494 1390 MXY
0 -27 Dl
-8 15 Dl
-16 1 Dl
24 11 Dl
-166 -265 Dl
3 f
3232 1617(LIBTP)N
2995 1390 MXY
0 400 Dl
666 0 Dl
0 -400 Dl
-666 0 Dl
992 MY
0 133 Dl
666 0 Dl
0 -133 Dl
-666 0 Dl
3168 1086(Application)N
1 f
2939 1201(txn_begin)N
2885 1284(txn_commit)N
2950 1368(txn_abort)N
3465 1284(db_ops)N
3 f
3155 766(Single)N
3339(Process)X
3 Dt
-1 Ds
811 2100(Figure)N
1023(2:)X
1107(Server)X
1318(Architecture.)X
1 f
1727(In)X
1811(this)X
1934(con\256guration,)X
811 2190(the)N
916(library)X
1113(is)X
1183(loaded)X
1380(into)X
1507(a)X
1562(server)X
1744(process)X
1962(which)X
2145(is)X
2214(ac-)X
811 2280(cessed)N
993(via)X
1087(a)X
1131(socket)X
1310(interface.)X
3 f
2563 2100(Figure)N
2803(3:)X
2914(Single)X
3140(Process)X
3403(Architecture.)X
1 f
3839(In)X
3950(this)X
2563 2190(con\256guration,)N
2948(the)X
3053(library)X
3250(routines)X
3483(are)X
3587(loaded)X
3784(as)X
3864(part)X
3990(of)X
2563 2280(the)N
2657(application)X
2957(and)X
3065(accessed)X
3303(via)X
3397(a)X
3441(subroutine)X
3727(interface.)X
10 s
10 f
555 2403(h)N
579(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)X
1 f
555 2679(modifying)N
909(a)X
966(piece)X
1157(of)X
1245(data)X
1400(would)X
1621(require)X
1870(three)X
2051(or)X
2138(possibly)X
2424(four)X
2578(separate)X
2862(communications:)X
3433(one)X
3569(to)X
3651(lock)X
3809(the)X
3927(data,)X
4101(one)X
4237(to)X
555 2769(obtain)N
781(the)X
905(data,)X
1085(one)X
1227(to)X
1315(log)X
1443(the)X
1567(modi\256cation,)X
2017(and)X
2159(possibly)X
2451(one)X
2593(to)X
2681(transmit)X
2969(the)X
3093(modi\256ed)X
3403(data.)X
3583(Figure)X
3817(four)X
3976(shows)X
4201(the)X
555 2859(relative)N
826(performance)X
1263(for)X
1387(retrieving)X
1728(a)X
1793(single)X
2013(record)X
2248(using)X
2450(the)X
2577(record)X
2812(level)X
2997(call)X
3142(versus)X
3376(using)X
3578(the)X
3705(lower)X
3917(level)X
4102(buffer)X
555 2949(management)N
987(and)X
1125(locking)X
1387(calls.)X
1616(The)X
1763(2:1)X
1887(ratio)X
2056(observed)X
2367(in)X
2450(the)X
2569(single)X
2781(process)X
3043(case)X
3203(re\257ects)X
3456(the)X
3575(additional)X
3916(overhead)X
4232(of)X
555 3039(parsing)N
819(eight)X
1006(commands)X
1380(rather)X
1595(than)X
1760(one)X
1903(while)X
2108(the)X
2233(3:1)X
2362(ratio)X
2536(observed)X
2853(in)X
2942(the)X
3067(client/server)X
3491(architecture)X
3898(re\257ects)X
4157(both)X
555 3129(the)N
679(parsing)X
941(and)X
1083(the)X
1207(communication)X
1731(overheard.)X
2118(Although)X
2445(there)X
2631(may)X
2794(be)X
2895(applications)X
3307(which)X
3528(could)X
3731(tolerate)X
3997(such)X
4169(per-)X
555 3219(formance,)N
904(it)X
973(seems)X
1194(far)X
1309(more)X
1499(feasible)X
1774(to)X
1861(support)X
2126(a)X
2187(higher)X
2417(level)X
2597(interface,)X
2923(such)X
3094(as)X
3185(that)X
3329(provided)X
3638(by)X
3742(a)X
3802(query)X
4009(language)X
555 3309(\()N
2 f
582(e.g.)X
1 f
718(SQL)X
889([SQL86]\).)X
755 3432(Although)N
1081(LIBTP)X
1327(does)X
1498(not)X
1624(have)X
1800(an)X
1900(SQL)X
2075(parser,)X
2316(we)X
2433(have)X
2608(built)X
2777(a)X
2836(server)X
3056(application)X
3435(using)X
3631(the)X
3752(toolkit)X
3983(command)X
555 3522(language)N
882(\(TCL\))X
1124([OUST90].)X
1544(The)X
1706(server)X
1940(supports)X
2248(a)X
2321(command)X
2674(line)X
2831(interface)X
3150(similar)X
3409(to)X
3508(the)X
3643(subroutine)X
4017(interface)X
555 3612(de\256ned)N
811(in)X
3 f
893(db)X
1 f
981(\(3\).)X
1135(Since)X
1333(it)X
1397(is)X
1470(based)X
1673(on)X
1773(TCL,)X
1964(it)X
2028(provides)X
2324(control)X
2571(structures)X
2903(as)X
2990(well.)X
3 f
555 3798(4.)N
655(Implementation)X
1 f
3 f
555 3984(4.1.)N
715(Locking)X
1014(and)X
1162(Deadlock)X
1502(Detection)X
1 f
755 4107(LIBTP)N
1007(uses)X
1175(two-phase)X
1535(locking)X
1805(for)X
1929(user)X
2093(data.)X
2297(Strictly)X
2562(speaking,)X
2897(the)X
3024(two)X
3173(phases)X
3416(in)X
3507(two-phase)X
3866(locking)X
4135(are)X
4263(a)X
3 f
555 4197(grow)N
1 f
756(phase,)X
986(during)X
1221(which)X
1443(locks)X
1638(are)X
1763(acquired,)X
2086(and)X
2228(a)X
3 f
2290(shrink)X
1 f
2537(phase,)X
2766(during)X
3001(which)X
3223(locks)X
3418(are)X
3543(released.)X
3873(No)X
3997(lock)X
4161(may)X
555 4287(ever)N
720(be)X
822(acquired)X
1124(during)X
1358(the)X
1481(shrink)X
1706(phase.)X
1954(The)X
2104(grow)X
2294(phase)X
2502(lasts)X
2669(until)X
2840(the)X
2963(\256rst)X
3112(release,)X
3381(which)X
3602(marks)X
3823(the)X
3946(start)X
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4201(the)X
555 4377(shrink)N
780(phase.)X
1028(In)X
1120(practice,)X
1420(the)X
1543(grow)X
1733(phase)X
1941(lasts)X
2108(for)X
2227(the)X
2350(duration)X
2642(of)X
2734(a)X
2795(transaction)X
3172(in)X
3259(LIBTP)X
3506(and)X
3647(in)X
3734(commercial)X
4138(data-)X
555 4467(base)N
721(systems.)X
1037(The)X
1184(shrink)X
1406(phase)X
1611(takes)X
1798(place)X
1990(during)X
2221(transaction)X
2595(commit)X
2861(or)X
2950(abort.)X
3177(This)X
3341(means)X
3568(that)X
3710(locks)X
3901(are)X
4022(acquired)X
555 4557(on)N
655(demand)X
929(during)X
1158(the)X
1276(lifetime)X
1545(of)X
1632(a)X
1688(transaction,)X
2080(and)X
2216(held)X
2374(until)X
2540(commit)X
2804(time,)X
2986(at)X
3064(which)X
3280(point)X
3464(all)X
3564(locks)X
3753(are)X
3872(released.)X
755 4680(If)N
832(multiple)X
1121(transactions)X
1527(are)X
1649(active)X
1864(concurrently,)X
2313(deadlocks)X
2657(can)X
2792(occur)X
2994(and)X
3133(must)X
3311(be)X
3410(detected)X
3701(and)X
3840(resolved.)X
4174(The)X
555 4770(lock)N
715(table)X
893(can)X
1027(be)X
1125(thought)X
1391(of)X
1480(as)X
1569(a)X
1627(representation)X
2104(of)X
2193(a)X
2251(directed)X
2532(graph.)X
2777(The)X
2924(nodes)X
3133(in)X
3216(the)X
3335(graph)X
3539(are)X
3659(transactions.)X
4103(Edges)X
555 4860(represent)N
878(the)X
3 f
1004(waits-for)X
1 f
1340(relation)X
1613(between)X
1909(transactions;)X
2342(if)X
2419(transaction)X
2 f
2799(A)X
1 f
2876(is)X
2957(waiting)X
3225(for)X
3347(a)X
3411(lock)X
3577(held)X
3743(by)X
3851(transaction)X
2 f
4230(B)X
1 f
4279(,)X
555 4950(then)N
716(a)X
775(directed)X
1057(edge)X
1232(exists)X
1437(from)X
2 f
1616(A)X
1 f
1687(to)X
2 f
1771(B)X
1 f
1842(in)X
1926(the)X
2046(graph.)X
2291(A)X
2371(deadlock)X
2683(exists)X
2887(if)X
2958(a)X
3016(cycle)X
3208(appears)X
3476(in)X
3560(the)X
3680(graph.)X
3925(By)X
4040(conven-)X
555 5040(tion,)N
719(no)X
819(transaction)X
1191(ever)X
1350(waits)X
1539(for)X
1653(a)X
1709(lock)X
1867(it)X
1931(already)X
2188(holds,)X
2401(so)X
2492(re\257exive)X
2793(edges)X
2996(are)X
3115(impossible.)X
755 5163(A)N
836(distinguished)X
1285(process)X
1549(monitors)X
1856(the)X
1977(lock)X
2138(table,)X
2337(searching)X
2668(for)X
2785(cycles.)X
3048(The)X
3195(frequency)X
3539(with)X
3703(which)X
3921(this)X
4058(process)X
555 5253(runs)N
716(is)X
792(user-settable;)X
1243(for)X
1360(the)X
1481(multi-user)X
1833(tests)X
1998(discussed)X
2328(in)X
2413(section)X
2663(5.1.2,)X
2866(it)X
2933(has)X
3063(been)X
3238(set)X
3350(to)X
3435(wake)X
3628(up)X
3731(every)X
3932(second,)X
4197(but)X
555 5343(more)N
742(sophisticated)X
1182(schedules)X
1516(are)X
1636(certainly)X
1938(possible.)X
2261(When)X
2474(a)X
2531(cycle)X
2722(is)X
2796(detected,)X
3105(one)X
3242(of)X
3330(the)X
3449(transactions)X
3853(in)X
3936(the)X
4055(cycle)X
4246(is)X
555 5433(nominated)N
917(and)X
1057(aborted.)X
1362(When)X
1578(the)X
1700(transaction)X
2076(aborts,)X
2315(it)X
2382(rolls)X
2547(back)X
2722(its)X
2820(changes)X
3102(and)X
3241(releases)X
3519(its)X
3617(locks,)X
3829(thereby)X
4093(break-)X
555 5523(ing)N
677(the)X
795(cycle)X
985(in)X
1067(the)X
1185(graph.)X
8 p
10 s 10 xH 0 xS 1 f
3 f
1 f
4 Ds
1 Dt
1866 865 MXY
1338 0 Dl
1866 1031 MXY
1338 0 Dl
1866 1199 MXY
1338 0 Dl
1866 1366 MXY
1338 0 Dl
1866 1533 MXY
1338 0 Dl
1866 1701 MXY
1338 0 Dl
-1 Ds
5 Dt
1866 1868 MXY
1338 0 Dl
1 Dt
1 Di
2981 MX
2981 1868 lineto
2981 1575 lineto
3092 1575 lineto
3092 1868 lineto
2981 1868 lineto
closepath 21 2981 1575 3092 1868 Dp
2646 MX
2646 1868 lineto
2646 949 lineto
2758 949 lineto
2758 1868 lineto
2646 1868 lineto
closepath 14 2646 949 2758 1868 Dp
2312 MX
2312 1868 lineto
2312 1701 lineto
2423 1701 lineto
2423 1868 lineto
2312 1868 lineto
closepath 3 2312 1701 2423 1868 Dp
1977 MX
1977 1868 lineto
1977 1512 lineto
2089 1512 lineto
2089 1868 lineto
1977 1868 lineto
closepath 19 1977 1512 2089 1868 Dp
3 f
2640 2047(Client/Server)N
1957(Single)X
2185(Process)X
7 s
2957 1957(record)N
2570(component)X
2289(record)X
1890(components)X
1733 1724(.1)N
1733 1556(.2)N
1733 1389(.3)N
1733 1222(.4)N
1733 1055(.5)N
1733 889(.6)N
1590 726(Elapsed)N
1794(Time)X
1613 782(\(in)N
1693(seconds\))X
3 Dt
-1 Ds
8 s
555 2255(Figure)N
756(4:)X
829(Comparison)X
1187(of)X
1260(High)X
1416(and)X
1540(Low)X
1681(Level)X
1850(Interfaces.)X
1 f
2174(Elapsed)X
2395(time)X
2528(in)X
2597(seconds)X
2818(to)X
2887(perform)X
3111(a)X
3158(single)X
3330(record)X
3511(retrieval)X
3742(from)X
3885(a)X
3932(command)X
4203(line)X
555 2345(\(rather)N
751(than)X
888(a)X
943(procedural)X
1241(interface\))X
1510(is)X
1579(shown)X
1772(on)X
1862(the)X
1966(y)X
2024(axis.)X
2185(The)X
2310(``component'')X
2704(numbers)X
2950(re\257ect)X
3135(the)X
3239(timings)X
3458(when)X
3622(the)X
3726(record)X
3914(is)X
3983(retrieved)X
4235(by)X
555 2435(separate)N
785(calls)X
924(to)X
996(the)X
1096(lock)X
1228(manager)X
1469(and)X
1583(buffer)X
1760(manager)X
2001(while)X
2165(the)X
2264(``record'')X
2531(timings)X
2745(were)X
2889(obtained)X
3130(by)X
3215(using)X
3375(a)X
3424(single)X
3598(call)X
3711(to)X
3782(the)X
3881(record)X
4064(manager.)X
555 2525(The)N
674(2:1)X
776(ratio)X
913(observed)X
1163(for)X
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1355(single)X
1528(process)X
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1930(a)X
1977(re\257ection)X
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2309(the)X
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2613(overhead)X
2865(for)X
2958(executing)X
3225(eight)X
3372(separate)X
3599(commands)X
3895(rather)X
4062(than)X
4191(one.)X
555 2615(The)N
673(additional)X
948(factor)X
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1187(one)X
1298(re\257ected)X
1536(in)X
1605(the)X
1702(3:1)X
1803(ratio)X
1939(for)X
2031(the)X
2127(client/server)X
2460(architecture)X
2794(is)X
2855(due)X
2965(to)X
3033(the)X
3129(communication)X
3545(overhead.)X
3828(The)X
3945(true)X
4062(ratios)X
4222(are)X
555 2705(actually)N
775(worse)X
945(since)X
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1492(timings)X
1703(do)X
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1884(re\257ect)X
2060(the)X
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2334(times)X
2490(within)X
2671(each)X
2804(page)X
2941(or)X
3011(the)X
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3237(required)X
3466(to)X
3533(transmit)X
3760(the)X
3855(page)X
3992(between)X
4221(the)X
555 2795(two)N
667(processes.)X
10 s
10 f
555 2885(h)N
579(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)X
3 f
555 3161(4.2.)N
715(Group)X
961(Commit)X
1 f
755 3284(Since)N
959(the)X
1083(log)X
1211(must)X
1392(be)X
1494(\257ushed)X
1751(to)X
1839(disk)X
1997(at)X
2080(commit)X
2349(time,)X
2536(disk)X
2694(bandwidth)X
3057(fundamentally)X
3545(limits)X
3751(the)X
3874(rate)X
4020(at)X
4103(which)X
555 3374(transactions)N
959(complete.)X
1314(Since)X
1513(most)X
1688(transactions)X
2091(write)X
2276(only)X
2438(a)X
2494(few)X
2635(small)X
2828(records)X
3085(to)X
3167(the)X
3285(log,)X
3427(the)X
3545(last)X
3676(page)X
3848(of)X
3935(the)X
4053(log)X
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3841(would)X
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555 3554(serially.)N
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3 f
1177(group)X
1412(commit)X
1 f
1702([DEWI84])X
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555 3767(multiple)N
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3137(page,)X
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555 3947(semaphore.)N
966(Later,)X
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1629(transaction)X
2004(\257ushes)X
2249(the)X
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2545(to)X
2630(disk,)X
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3400(group)X
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3935(and)X
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555 4127(the)N
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1855(wait)X
2021(threshold)X
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2352(which)X
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1950(logdelay)X
2257(threshold)X
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2590(which)X
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555 4397(allowed)N
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2852(\257ushed.)X
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1803(improve)X
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2517(for)X
2631(high-concurrency)X
3218(environments.)X
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555 4610(sactions)N
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957(running,)X
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2632(crossover)X
2962(point)X
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555 4700(commit)N
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1974(the)X
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677(faster)X
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1959(then)X
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2732(increase)X
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3398(rate.)X
3 f
555 4976(4.3.)N
715(Kernel)X
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1418(for)X
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1 f
755 5099(Since)N
954(LIBTP)X
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2140(e.g.)X
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2277(the)X
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555 5279(processes)N
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555 5385(tion)N
705(under)X
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7 s
5353(2)Y
10 s
5385(,)Y
1305(we)X
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2303(to)X
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4237(in)X
555 5475(this)N
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3732(to)X
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8 s
10 f
555 5547(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)N
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1 f
727 5625(2)N
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763 5650(Ultrix)N
932(and)X
1040(DEC)X
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1277(trademarks)X
1576(of)X
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1839(Equipment)X
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9 p
8 s 8 xH 0 xS 1 f
10 s
3 f
1 f
555 630(executes)N
852(atomically)X
1210(there.)X
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878(architectures)X
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924(uncontested)X
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4007(example,)X
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885(must)X
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3297(pin)X
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3698(in)X
3781(shared)X
4012(memory.)X
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555 1293(tion,)N
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2998(to)X
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4263(a)X
555 1776(600MByte)N
920(HP7959)X
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3141(comparisons)X
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3389(express)X
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555 2586(TPS,)N
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635 2799(g)N
1 f
755(even)X
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635 2922(g)N
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755(when)X
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2436(\(67%\).)X
3 f
555 3108(4.4.)N
715(Transaction)X
1148(Protected)X
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1 f
755 3231(The)N
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10 f
555 3507(h)N
579(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)X
1 Dt
2978 5036 MXY
2978 5036 lineto
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closepath 21 2978 4662 3093 5036 Dp
2518 MX
2518 5036 lineto
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closepath 3 2518 3960 2633 5036 Dp
2059 MX
2059 5036 lineto
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2059 5036 lineto
closepath 1 2059 3946 2174 5036 Dp
3 f
7 s
2912 5141(Read-only)N
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1786(as)X
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11 s
1670 4843(20)N
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2041 5141(1)N
2083(Disk)X
2490(2)X
2532(Disks)X
5 Dt
1829 5036 MXY
1494 0 Dl
4 Ds
1 Dt
1829 4806 MXY
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1829 4347 MXY
1494 0 Dl
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1494 0 Dl
1829 3888 MXY
1494 0 Dl
3 Dt
-1 Ds
8 s
555 5360(Figure)N
753(5:)X
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2254(The)X
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10 p
8 s 8 xH 0 xS 1 f
10 s
3 f
1 f
555 630(access)N
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2285(with)X
2447(the)X
2565(following)X
2896(calling)X
3134(conventions:)X
7 f
715 753(DB)N
859(*dbopen)X
1243(\(const)X
1579(char)X
1819(*file,)X
2155(int)X
2347(flags,)X
2683(int)X
2875(mode,)X
3163(DBTYPE)X
3499(type,)X
1291 843(int)N
1483(dbflags,)X
1915(const)X
2203(void)X
2443(*openinfo\))X
1 f
555 966(where)N
2 f
774(\256le)X
1 f
894(is)X
969(the)X
1089(name)X
1285(of)X
1374(the)X
1494(\256le)X
1618(being)X
1818(opened,)X
2 f
2092(\257ags)X
1 f
2265(and)X
2 f
2402(mode)X
1 f
2597(are)X
2717(the)X
2836(standard)X
3129(arguments)X
3484(to)X
3 f
3567(open)X
1 f
3731(\(2\),)X
2 f
3866(type)X
1 f
4021(is)X
4095(one)X
4232(of)X
555 1056(the)N
680(access)X
913(method)X
1180(types,)X
2 f
1396(db\257ags)X
1 f
1654(indicates)X
1966(the)X
2091(mode)X
2296(of)X
2390(the)X
2515(buffer)X
2739(pool)X
2907(and)X
3049(transaction)X
3427(protection,)X
3798(and)X
2 f
3940(openinfo)X
1 f
4246(is)X
555 1146(the)N
681(access)X
915(method)X
1183(speci\256c)X
1456(information.)X
1902(Currently,)X
2257(the)X
2383(possible)X
2673(values)X
2906(for)X
2 f
3028(db\257ags)X
1 f
3287(are)X
3414(DB_SHARED)X
3912(and)X
4055(DB_TP)X
555 1236(indicating)N
895(that)X
1035(buffers)X
1283(should)X
1516(be)X
1612(kept)X
1770(in)X
1852(a)X
1908(shared)X
2138(buffer)X
2355(pool)X
2517(and)X
2653(that)X
2793(the)X
2911(\256le)X
3033(should)X
3266(be)X
3362(transaction)X
3734(protected.)X
755 1359(The)N
900(modi\256cations)X
1355(required)X
1643(to)X
1725(add)X
1861(transaction)X
2233(protection)X
2578(to)X
2660(an)X
2756(access)X
2982(method)X
3242(are)X
3361(quite)X
3541(simple)X
3774(and)X
3910(localized.)X
715 1482(1.)N
795(Replace)X
1074(\256le)X
2 f
1196(open)X
1 f
1372(with)X
2 f
1534(buf_open)X
1 f
1832(.)X
715 1572(2.)N
795(Replace)X
1074(\256le)X
2 f
1196(read)X
1 f
1363(and)X
2 f
1499(write)X
1 f
1683(calls)X
1850(with)X
2012(buffer)X
2229(manager)X
2526(calls)X
2693(\()X
2 f
2720(buf_get)X
1 f
(,)S
2 f
3000(buf_unpin)X
1 f
3324(\).)X
715 1662(3.)N
795(Precede)X
1070(buffer)X
1287(manager)X
1584(calls)X
1751(with)X
1913(an)X
2009(appropriate)X
2395(\(read)X
2581(or)X
2668(write\))X
2880(lock)X
3038(call.)X
715 1752(4.)N
795(Before)X
1034(updates,)X
1319(issue)X
1499(a)X
1555(logging)X
1819(operation.)X
715 1842(5.)N
795(After)X
985(data)X
1139(have)X
1311(been)X
1483(accessed,)X
1805(release)X
2049(the)X
2167(buffer)X
2384(manager)X
2681(pin.)X
715 1932(6.)N
795(Provide)X
1064(undo/redo)X
1409(code)X
1581(for)X
1695(each)X
1863(type)X
2021(of)X
2108(log)X
2230(record)X
2456(de\256ned.)X
555 2071(The)N
702(following)X
1035(code)X
1209(fragments)X
1552(show)X
1743(how)X
1903(to)X
1987(transaction)X
2361(protect)X
2606(several)X
2856(updates)X
3123(to)X
3206(a)X
3263(B-tree.)X
7 s
3484 2039(3)N
10 s
3533 2071(In)N
3621(the)X
3740(unprotected)X
4140(case,)X
555 2161(an)N
652(open)X
829(call)X
966(is)X
1040(followed)X
1346(by)X
1447(a)X
1504(read)X
1664(call)X
1801(to)X
1884(obtain)X
2105(the)X
2224(meta-data)X
2562(for)X
2677(the)X
2796(B-tree.)X
3058(Instead,)X
3331(we)X
3446(issue)X
3627(an)X
3724(open)X
3901(to)X
3984(the)X
4102(buffer)X
555 2251(manager)N
852(to)X
934(obtain)X
1154(a)X
1210(\256le)X
1332(id)X
1414(and)X
1550(a)X
1606(buffer)X
1823(request)X
2075(to)X
2157(obtain)X
2377(the)X
2495(meta-data)X
2832(as)X
2919(shown)X
3148(below.)X
7 f
715 2374(char)N
955(*path;)X
715 2464(int)N
907(fid,)X
1147(flags,)X
1483(len,)X
1723(mode;)X
715 2644(/*)N
859(Obtain)X
1195(a)X
1291(file)X
1531(id)X
1675(with)X
1915(which)X
2203(to)X
2347(access)X
2683(the)X
2875(buffer)X
3211(pool)X
3451(*/)X
715 2734(fid)N
907(=)X
1003(buf_open\(path,)X
1723(flags,)X
2059(mode\);)X
715 2914(/*)N
859(Read)X
1099(the)X
1291(meta)X
1531(data)X
1771(\(page)X
2059(0\))X
2203(for)X
2395(the)X
2587(B-tree)X
2923(*/)X
715 3004(if)N
859(\(tp_lock\(fid,)X
1531(0,)X
1675(READ_LOCK\)\))X
1003 3094(return)N
1339(error;)X
715 3184(meta_data_ptr)N
1387(=)X
1483(buf_get\(fid,)X
2107(0,)X
2251(BF_PIN,)X
2635(&len\);)X
1 f
555 3307(The)N
714(BF_PIN)X
1014(argument)X
1350(to)X
2 f
1445(buf_get)X
1 f
1718(indicates)X
2036(that)X
2189(we)X
2316(wish)X
2500(to)X
2595(leave)X
2798(this)X
2946(page)X
3131(pinned)X
3382(in)X
3477(memory)X
3777(so)X
3881(that)X
4034(it)X
4111(is)X
4197(not)X
555 3397(swapped)N
862(out)X
990(while)X
1194(we)X
1314(are)X
1439(accessing)X
1772(it.)X
1881(The)X
2031(last)X
2167(argument)X
2495(to)X
2 f
2582(buf_get)X
1 f
2847(returns)X
3095(the)X
3218(number)X
3488(of)X
3580(bytes)X
3774(on)X
3879(the)X
4002(page)X
4179(that)X
555 3487(were)N
732(valid)X
912(so)X
1003(that)X
1143(the)X
1261(access)X
1487(method)X
1747(may)X
1905(initialize)X
2205(the)X
2323(page)X
2495(if)X
2564(necessary.)X
755 3610(Next,)N
955(consider)X
1251(inserting)X
1555(a)X
1615(record)X
1845(on)X
1949(a)X
2009(particular)X
2341(page)X
2517(of)X
2608(a)X
2668(B-tree.)X
2932(In)X
3022(the)X
3143(unprotected)X
3545(case,)X
3727(we)X
3844(read)X
4006(the)X
4127(page,)X
555 3700(call)N
2 f
693(_bt_insertat)X
1 f
1079(,)X
1121(and)X
1258(write)X
1444(the)X
1563(page.)X
1776(Instead,)X
2049(we)X
2164(lock)X
2323(the)X
2442(page,)X
2635(request)X
2888(the)X
3007(buffer,)X
3245(log)X
3368(the)X
3487(change,)X
3756(modify)X
4008(the)X
4127(page,)X
555 3790(and)N
691(release)X
935(the)X
1053(buffer.)X
7 f
715 3913(int)N
907(fid,)X
1147(len,)X
1387(pageno;)X
1867(/*)X
2011(Identifies)X
2539(the)X
2731(buffer)X
3067(*/)X
715 4003(int)N
907(index;)X
1867(/*)X
2011(Location)X
2443(at)X
2587(which)X
2875(to)X
3019(insert)X
3355(the)X
3547(new)X
3739(pair)X
3979(*/)X
715 4093(DBT)N
907(*keyp,)X
1243(*datap;)X
1867(/*)X
2011(Key/Data)X
2443(pair)X
2683(to)X
2827(be)X
2971(inserted)X
3403(*/)X
715 4183(DATUM)N
1003(*d;)X
1867(/*)X
2011(Key/data)X
2443(structure)X
2923(to)X
3067(insert)X
3403(*/)X
715 4363(/*)N
859(Lock)X
1099(and)X
1291(request)X
1675(the)X
1867(buffer)X
2203(*/)X
715 4453(if)N
859(\(tp_lock\(fid,)X
1531(pageno,)X
1915(WRITE_LOCK\)\))X
1003 4543(return)N
1339(error;)X
715 4633(buffer_ptr)N
1243(=)X
1339(buf_get\(fid,)X
1963(pageno,)X
2347(BF_PIN,)X
2731(&len\);)X
715 4813(/*)N
859(Log)X
1051(and)X
1243(perform)X
1627(the)X
1819(update)X
2155(*/)X
715 4903(log_insdel\(BTREE_INSERT,)N
1915(fid,)X
2155(pageno,)X
2539(keyp,)X
2827(datap\);)X
715 4993(_bt_insertat\(buffer_ptr,)N
1915(d,)X
2059(index\);)X
715 5083(buf_unpin\(buffer_ptr\);)N
1 f
555 5206(Succinctly,)N
942(the)X
1068(algorithm)X
1407(for)X
1529(turning)X
1788(unprotected)X
2195(code)X
2375(into)X
2527(protected)X
2854(code)X
3034(is)X
3115(to)X
3205(replace)X
3466(read)X
3633(operations)X
3995(with)X
2 f
4165(lock)X
1 f
555 5296(and)N
2 f
691(buf_get)X
1 f
951(operations)X
1305(and)X
1441(write)X
1626(operations)X
1980(with)X
2 f
2142(log)X
1 f
2264(and)X
2 f
2400(buf_unpin)X
1 f
2744(operations.)X
8 s
10 f
555 5458(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)N
5 s
1 f
727 5536(3)N
8 s
766 5561(The)N
884(following)X
1152(code)X
1291(fragments)X
1565(are)X
1661(examples,)X
1937(but)X
2038(do)X
2120(not)X
2220(de\256ne)X
2394(the)X
2490(\256nal)X
2622(interface.)X
2894(The)X
3011(\256nal)X
3143(interface)X
3383(will)X
3501(be)X
3579(determined)X
3884(after)X
4018(LIBTP)X
4214(has)X
555 5633(been)N
691(fully)X
828(integrated)X
1099(with)X
1229(the)X
1323(most)X
1464(recent)X
3 f
1635(db)X
1 f
1707(\(3\))X
1797(release)X
1989(from)X
2129(the)X
2223(Computer)X
2495(Systems)X
2725(Research)X
2974(Group)X
3153(at)X
3215(University)X
3501(of)X
3570(California,)X
3861(Berkeley.)X
11 p
8 s 8 xH 0 xS 1 f
10 s
3 f
555 630(5.)N
655(Performance)X
1 f
755 753(In)N
845(this)X
983(section,)X
1253(we)X
1370(present)X
1625(the)X
1746(results)X
1978(of)X
2067(two)X
2209(very)X
2374(different)X
2673(benchmarks.)X
3103(The)X
3250(\256rst)X
3396(is)X
3471(an)X
3569(online)X
3791(transaction)X
4165(pro-)X
555 843(cessing)N
824(benchmark,)X
1234(similar)X
1489(to)X
1584(the)X
1715(standard)X
2020(TPCB,)X
2272(but)X
2407(has)X
2547(been)X
2732(adapted)X
3015(to)X
3110(run)X
3250(in)X
3345(a)X
3414(desktop)X
3696(environment.)X
4174(The)X
555 933(second)N
798(emulates)X
1103(a)X
1159(computer-aided)X
1683(design)X
1912(environment)X
2337(and)X
2473(provides)X
2769(more)X
2954(complex)X
3250(query)X
3453(processing.)X
3 f
555 1119(5.1.)N
715(Transaction)X
1148(Processing)X
1533(Benchmark)X
1 f
755 1242(For)N
887(this)X
1023(section,)X
1291(all)X
1392(performance)X
1820(numbers)X
2117(shown)X
2346(except)X
2576(for)X
2690(the)X
2808(commercial)X
3207(database)X
3504(system)X
3746(were)X
3923(obtained)X
4219(on)X
555 1332(a)N
614(DECstation)X
1009(5000/200)X
1333(with)X
1497(32MBytes)X
1852(of)X
1941(memory)X
2230(running)X
2501(Ultrix)X
2714(V4.0,)X
2914(accessing)X
3244(a)X
3302(DEC)X
3484(RZ57)X
3688(1GByte)X
3959(disk)X
4114(drive.)X
555 1422(The)N
720(commercial)X
1139(relational)X
1482(database)X
1799(system)X
2061(tests)X
2242(were)X
2438(run)X
2584(on)X
2703(a)X
2778(comparable)X
3192(machine,)X
3523(a)X
3598(Sparcstation)X
4033(1+)X
4157(with)X
555 1512(32MBytes)N
915(memory)X
1209(and)X
1352(a)X
1415(1GByte)X
1691(external)X
1976(disk)X
2135(drive.)X
2366(The)X
2517(database,)X
2840(binaries)X
3120(and)X
3262(log)X
3390(resided)X
3648(on)X
3754(the)X
3878(same)X
4069(device.)X
555 1602(Reported)N
869(times)X
1062(are)X
1181(the)X
1299(means)X
1524(of)X
1611(\256ve)X
1751(tests)X
1913(and)X
2049(have)X
2221(standard)X
2513(deviations)X
2862(within)X
3086(two)X
3226(percent)X
3483(of)X
3570(the)X
3688(mean.)X
755 1725(The)N
905(test)X
1041(database)X
1343(was)X
1493(con\256gured)X
1861(according)X
2203(to)X
2290(the)X
2413(TPCB)X
2637(scaling)X
2889(rules)X
3070(for)X
3189(a)X
3250(10)X
3355(transaction)X
3732(per)X
3860(second)X
4108(\(TPS\))X
555 1815(system)N
817(with)X
999(1,000,000)X
1359(account)X
1649(records,)X
1946(100)X
2106(teller)X
2311(records,)X
2607(and)X
2762(10)X
2881(branch)X
3139(records.)X
3455(Where)X
3709(TPS)X
3885(numbers)X
4200(are)X
555 1905(reported,)N
865(we)X
981(are)X
1102(running)X
1373(a)X
1431(modi\256ed)X
1737(version)X
1995(of)X
2084(the)X
2203(industry)X
2486(standard)X
2779(transaction)X
3152(processing)X
3516(benchmark,)X
3914(TPCB.)X
4174(The)X
555 1995(TPCB)N
780(benchmark)X
1163(simulates)X
1491(a)X
1553(withdrawal)X
1940(performed)X
2301(by)X
2407(a)X
2469(hypothetical)X
2891(teller)X
3082(at)X
3166(a)X
3228(hypothetical)X
3650(bank.)X
3872(The)X
4022(database)X
555 2085(consists)N
831(of)X
921(relations)X
1220(\(\256les\))X
1430(for)X
1547(accounts,)X
1871(branches,)X
2200(tellers,)X
2439(and)X
2578(history.)X
2863(For)X
2997(each)X
3168(transaction,)X
3563(the)X
3684(account,)X
3976(teller,)X
4183(and)X
555 2175(branch)N
795(balances)X
1093(must)X
1269(be)X
1366(updated)X
1641(to)X
1724(re\257ect)X
1946(the)X
2065(withdrawal)X
2447(and)X
2584(a)X
2640(history)X
2882(record)X
3108(is)X
3181(written)X
3428(which)X
3644(contains)X
3931(the)X
4049(account)X
555 2265(id,)N
657(branch)X
896(id,)X
998(teller)X
1183(id,)X
1285(and)X
1421(the)X
1539(amount)X
1799(of)X
1886(the)X
2004(withdrawal)X
2385([TPCB90].)X
755 2388(Our)N
914(implementation)X
1450(of)X
1551(the)X
1683(benchmark)X
2074(differs)X
2317(from)X
2506(the)X
2637(speci\256cation)X
3075(in)X
3170(several)X
3431(aspects.)X
3736(The)X
3894(speci\256cation)X
555 2478(requires)N
840(that)X
985(the)X
1108(database)X
1410(keep)X
1587(redundant)X
1933(logs)X
2091(on)X
2196(different)X
2498(devices,)X
2784(but)X
2911(we)X
3030(use)X
3162(a)X
3223(single)X
3439(log.)X
3606(Furthermore,)X
4052(all)X
4157(tests)X
555 2568(were)N
734(run)X
863(on)X
965(a)X
1023(single,)X
1256(centralized)X
1631(system)X
1875(so)X
1968(there)X
2151(is)X
2226(no)X
2328(notion)X
2553(of)X
2641(remote)X
2885(accesses.)X
3219(Finally,)X
3486(we)X
3601(calculated)X
3948(throughput)X
555 2658(by)N
662(dividing)X
955(the)X
1080(total)X
1249(elapsed)X
1517(time)X
1686(by)X
1793(the)X
1918(number)X
2190(of)X
2284(transactions)X
2694(processed)X
3038(rather)X
3253(than)X
3418(by)X
3525(computing)X
3894(the)X
4018(response)X
555 2748(time)N
717(for)X
831(each)X
999(transaction.)X
755 2871(The)N
912(performance)X
1351(comparisons)X
1788(focus)X
1993(on)X
2104(traditional)X
2464(Unix)X
2655(techniques)X
3029(\(unprotected,)X
3486(using)X
3 f
3690(\257ock)X
1 f
3854(\(2\))X
3979(and)X
4126(using)X
3 f
555 2961(fsync)N
1 f
733(\(2\)\))X
884(and)X
1030(a)X
1096(commercial)X
1504(relational)X
1836(database)X
2142(system.)X
2433(Well-behaved)X
2913(applications)X
3329(using)X
3 f
3531(\257ock)X
1 f
3695(\(2\))X
3818(are)X
3946(guaranteed)X
555 3051(that)N
704(concurrent)X
1077(processes')X
1441(updates)X
1715(do)X
1824(not)X
1955(interact)X
2225(with)X
2396(one)X
2541(another,)X
2831(but)X
2962(no)X
3070(guarantees)X
3442(about)X
3648(atomicity)X
3978(are)X
4105(made.)X
555 3141(That)N
731(is,)X
833(if)X
911(the)X
1038(system)X
1289(crashes)X
1555(in)X
1646(mid-transaction,)X
2198(only)X
2369(parts)X
2554(of)X
2649(that)X
2797(transaction)X
3177(will)X
3329(be)X
3433(re\257ected)X
3738(in)X
3828(the)X
3954 0.3125(after-crash)AX
555 3231(state)N
725(of)X
815(the)X
936(database.)X
1276(The)X
1424(use)X
1554(of)X
3 f
1643(fsync)X
1 f
1821(\(2\))X
1937(at)X
2017(transaction)X
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3 f
555 3507(5.1.1.)N
775(Single-User)X
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1728(\257ock)X
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1728(fsync)X
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1371(\257ock)X
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1535(\(2\))X
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3523(\(2\))X
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10 s 10 xH 0 xS 1 f
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8 s
3500 2184(RDBMS)N
1 Dt
3553 2085 MXY
3553 2085 lineto
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2018 2184(SERVER)N
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0 917 Dl
122 0 Dl
0 -917 Dl
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1715 2184(TCL)N
2087 1534 MXY
2087 1534 lineto
2209 1534 lineto
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3187 MX
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3142 2184(FSYNC)N
2425(NOTP)X
2453 955 MXY
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closepath 21 2453 955 2576 2085 Dp
2820 1000 MXY
2820 1000 lineto
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closepath 14 2820 1000 2942 2085 Dp
5 Dt
1231 2085 MXY
2567 0 Dl
4 Ds
1 Dt
1231 1840 MXY
2567 0 Dl
1231 1596 MXY
2567 0 Dl
1231 1351 MXY
2567 0 Dl
1231 1108 MXY
2567 0 Dl
1231 863 MXY
2567 0 Dl
11 s
1087 1877(2)N
1087 1633(4)N
1087 1388(6)N
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1065 900(10)N
1028 763(TPS)N
-1 Ds
1353 2085 MXY
1353 2085 lineto
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closepath 3 1353 1151 1476 2085 Dp
8 s
1318 2184(LIBTP)N
2767(FLOCK)X
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10 s
1597 2399(Figure)N
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10 f
555 5595(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)N
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1 f
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10 s
3 f
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3187 2051 MXY
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3286 2028 MXY
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3384 1926 MXY
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3483 1910 MXY
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3581 1910 MXY
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9 0 Dl
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3680 1832 MXY
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0 -9 Dl
9 0 Dl
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3778 1909 MXY
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0 -9 Dl
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3877 1883 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
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3975 1679 MXY
0 17 Dl
0 -8 Dl
9 0 Dl
-18 0 Dl
4074 1487 MXY
0 17 Dl
0 -8 Dl
9 0 Dl
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5 Dt
3187 2060 MXY
99 -24 Dl
98 -101 Dl
99 -16 Dl
98 0 Dl
99 -78 Dl
98 77 Dl
99 -26 Dl
98 -204 Dl
99 -192 Dl
3 f
6 s
4088 1516(SMALL)N
3 Dt
3187 2051 MXY
0 18 Dl
0 -9 Dl
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3286 2051 MXY
0 18 Dl
0 -9 Dl
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3384 2041 MXY
0 18 Dl
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9 0 Dl
-18 0 Dl
3483 1990 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
3581 1843 MXY
0 17 Dl
0 -8 Dl
9 0 Dl
-18 0 Dl
3680 1578 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
3778 1496 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
3877 1430 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
3975 1269 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
4074 1070 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
1 Dt
3187 2060 MXY
99 0 Dl
98 -10 Dl
99 -51 Dl
98 -147 Dl
99 -265 Dl
98 -82 Dl
99 -66 Dl
98 -161 Dl
99 -199 Dl
4088 1099(LARGE)N
5 Dt
3089 2060 MXY
985 0 Dl
3089 MX
0 -1174 Dl
4 Ds
1 Dt
3581 2060 MXY
0 -1174 Dl
4074 2060 MXY
0 -1174 Dl
3089 1825 MXY
985 0 Dl
9 s
2993 1855(25)N
3089 1591 MXY
985 0 Dl
2993 1621(50)N
3089 1356 MXY
985 0 Dl
2993 1386(75)N
3089 1121 MXY
985 0 Dl
2957 1151(100)N
3089 886 MXY
985 0 Dl
2957 916(125)N
3281 2199(Multiprogramming)N
3071 2152(0)N
3569(5)X
4038(10)X
2859 787(Aborts)N
3089(per)X
3211(500)X
2901 847(transactions)N
-1 Ds
3 Dt
2037 1342 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2125 1358 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2213 1341 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2301 1191 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2388 1124 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-17 0 Dl
2476 1157 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2564 1157 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2652 1161 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2740 1153 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2828 1150 MXY
0 18 Dl
0 -9 Dl
8 0 Dl
-17 0 Dl
5 Dt
2037 1351 MXY
88 16 Dl
88 -17 Dl
88 -150 Dl
87 -67 Dl
88 33 Dl
88 0 Dl
88 4 Dl
88 -8 Dl
88 -3 Dl
6 s
2685 1234(READ-ONLY)N
3 Dt
2037 1464 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2125 1640 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2213 1854 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2301 1872 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2388 1871 MXY
0 17 Dl
0 -9 Dl
9 0 Dl
-17 0 Dl
2476 1933 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2564 1914 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2652 1903 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2740 1980 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
2828 2004 MXY
0 18 Dl
0 -9 Dl
8 0 Dl
-17 0 Dl
1 Dt
2037 1473 MXY
88 176 Dl
88 214 Dl
88 18 Dl
87 -2 Dl
88 63 Dl
88 -19 Dl
88 -11 Dl
88 77 Dl
88 24 Dl
2759 1997(NO-FSYNC)N
5 Dt
1949 2060 MXY
879 0 Dl
1949 MX
0 -1174 Dl
4 Ds
1 Dt
2388 2060 MXY
0 -1174 Dl
2828 2060 MXY
0 -1174 Dl
1949 1825 MXY
879 0 Dl
9 s
1842 1855(40)N
1949 1591 MXY
879 0 Dl
1842 1621(80)N
1949 1356 MXY
879 0 Dl
1806 1386(120)N
1949 1121 MXY
879 0 Dl
1806 1151(160)N
1949 886 MXY
879 0 Dl
1806 916(200)N
2088 2199(Multiprogramming)N
1844 863(in)N
1922(TPS)X
1761 792(Throughput)N
1931 2121(0)N
2370 2133(5)N
2792(10)X
6 s
1679 1833(LIBTP)N
-1 Ds
3 Dt
837 1019 MXY
0 17 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
929 878 MXY
0 17 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
1021 939 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
1113 1043 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
1205 1314 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
1297 1567 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
1389 1665 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
1481 1699 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
1573 1828 MXY
0 18 Dl
0 -9 Dl
9 0 Dl
-18 0 Dl
1665 1804 MXY
0 18 Dl
0 -9 Dl
8 0 Dl
-17 0 Dl
5 Dt
837 1027 MXY
92 -141 Dl
92 62 Dl
92 104 Dl
92 271 Dl
92 253 Dl
92 98 Dl
92 34 Dl
92 129 Dl
92 -24 Dl
745 2060 MXY
920 0 Dl
745 MX
0 -1174 Dl
4 Ds
1 Dt
1205 2060 MXY
0 -1174 Dl
1665 2060 MXY
0 -1174 Dl
745 1766 MXY
920 0 Dl
9 s
673 1796(3)N
745 1473 MXY
920 0 Dl
673 1503(5)N
745 1180 MXY
920 0 Dl
673 1210(8)N
745 886 MXY
920 0 Dl
637 916(10)N
905 2199(Multiprogramming)N
622 851(in)N
700(TPS)X
575 792(Throughput)N
733 2152(0)N
1196(5)X
1629(10)X
3 Dt
-1 Ds
8 s
655 2441(Figure)N
872(7:)X
960(Multi-user)X
1286(Performance.)X
1 f
655 2531(Since)N
825(the)X
931(con\256guration)X
1300(is)X
1371(completely)X
655 2621(disk)N
790(bound,)X
994(we)X
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1204(only)X
1345(a)X
1400(small)X
1566(im-)X
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964(by)X
1064(adding)X
1274(a)X
1337(second)X
1549(pro-)X
655 2801(cess.)N
849(Adding)X
1081(any)X
1213(more)X
1383(concurrent)X
655 2891(processes)N
935(causes)X
1137(performance)X
1493(degra-)X
655 2981(dation.)N
3 f
1927 2441(Figure)N
2149(8:)X
2243(Multi-user)X
2574(Performance)X
1927 2531(on)N
2021(a)X
2079(small)X
2251(database.)X
1 f
2551(With)X
2704(one)X
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1927 2621(cess,)N
2075(we)X
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2276(driving)X
2486(the)X
2589(CPU)X
2739(at)X
2810(96%)X
1927 2711(utilization)N
2215(leaving)X
2430(little)X
2575(room)X
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2838(im-)X
1927 2801(provement)N
2238(as)X
2328(the)X
2443(multiprogramming)X
1927 2891(level)N
2091(increases.)X
2396(In)X
2489(the)X
2607(NO-FSYNC)X
1927 2981(case,)N
2076(lock)X
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1927 3071(mance)N
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2194(soon)X
2339(as)X
2416(a)X
2468(second)X
2669(process)X
2884(is)X
1927 3161(added.)N
3 f
3199 2441(Figure)N
3405(9:)X
3482(Abort)X
3669(rates)X
3827(on)X
3919(the)X
4028(TPCB)X
3199 2531(Benchmark.)N
1 f
3589(The)X
3726(abort)X
3895(rate)X
4028(climbs)X
3199 2621(more)N
3366(quickly)X
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3704(the)X
3818(large)X
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3324(since)X
3491(processes)X
3771(are)X
3884(descheduled)X
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3409(frequently,)X
3766(allowing)X
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3459(to)X
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3619(for)X
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3803(same)X
3950(locks.)X
10 s
10 f
555 3284(h)N
579(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)X
1 f
555 3560(records,)N
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952(expect)X
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2697(NO-FSYNC)X
3120(line)X
3263(in)X
3348(\256gure)X
3557(eight)X
3739(demonstrates)X
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1022(Each)X
1209(additional)X
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2682(and)X
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3470(Figure)X
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1353(\(SMALL\),)X
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3737(number)X
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2214(off)X
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2641(eight\),)X
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3958(\(LARGE\),)X
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967(contributes)X
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1116(are)X
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4085(oppor-)X
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814(to)X
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2307(do)X
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2540(and)X
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3234(be)X
3333(descheduled)X
3753(during)X
3985(a)X
4044(transac-)X
555 4223(tion.)N
740(In)X
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3804(This)X
3967(provides)X
4263(a)X
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2668(deadlock.)X
3 f
555 4589(5.2.)N
715(The)X
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1052(Benchmark)X
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755 4712(The)N
903(TPCB)X
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706(processing)X
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2625(computer-aided)X
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2300(\))X
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3262(often)X
3448(exhibited)X
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779(Ten)X
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14 p
10 s 10 xH 0 xS 1 f
3 f
1 f
755 630(The)N
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2891(y)X
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555 1938(5.2.1.)N
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755 2061(The)N
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3165(program)X
3463(control)X
3716(statements.)X
4120(Data-)X
555 2331(base)N
718(commands)X
1085(are)X
1204(submitted)X
1539(to)X
1621(the)X
1739(backend)X
2027(and)X
2163(results)X
2392(are)X
2511(bound)X
2731(to)X
2813(program)X
3105(variables.)X
755 2454(The)N
903(parts)X
1082(table)X
1261(was)X
1409(stored)X
1628(as)X
1718(a)X
1776(B-tree)X
1999(indexed)X
2275(by)X
2 f
2377(id)X
1 f
2439(.)X
2501(The)X
2648(connection)X
3022(table)X
3200(was)X
3347(stored)X
3565(as)X
3654(a)X
3712(set)X
3823(of)X
3912(\256xed-length)X
555 2544(records)N
824(using)X
1029(the)X
1159(4.4BSD)X
1446(recno)X
1657(access)X
1895(method.)X
2207(In)X
2306(addition,)X
2620(two)X
2771(B-tree)X
3003(indices)X
3261(were)X
3449(maintained)X
3836(on)X
3947(connection)X
555 2634(table)N
732(entries.)X
1007(One)X
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1360(mapped)X
1634(the)X
2 f
1752(from)X
1 f
1923(\256eld)X
2085(to)X
2167(a)X
2223(connection)X
2595(record)X
2821(number,)X
3106(and)X
3242(the)X
3360(other)X
3545(mapped)X
3819(the)X
2 f
3937(to)X
1 f
4019(\256eld)X
4181(to)X
4263(a)X
555 2724(connection)N
932(record)X
1163(number.)X
1473(These)X
1690(indices)X
1941(support)X
2205(fast)X
2345(lookups)X
2622(on)X
2726(connections)X
3133(in)X
3219(both)X
3385(directions.)X
3765(For)X
3900(the)X
4022(traversal)X
555 2814(tests,)N
743(the)X
867(frontend)X
1165(does)X
1338(an)X
1439(index)X
1642(lookup)X
1889(to)X
1976(discover)X
2273(the)X
2396(connected)X
2747(part's)X
2 f
2955(id)X
1 f
3017(,)X
3062(and)X
3203(then)X
3366(does)X
3538(another)X
3804(lookup)X
4051(to)X
4138(fetch)X
555 2904(the)N
673(part)X
818(itself.)X
3 f
555 3090(5.2.2.)N
775(Performance)X
1242(Measurements)X
1766(for)X
1889(OO1)X
1 f
755 3213(We)N
888(compare)X
1186(LIBTP's)X
1487(OO1)X
1664(performance)X
2092(to)X
2174(that)X
2314(reported)X
2602(in)X
2684([CATT91].)X
3087(Those)X
3303(results)X
3532(were)X
3709(collected)X
4019(on)X
4119(a)X
4175(Sun)X
555 3303(3/280)N
759(\(25)X
888(MHz)X
1075(MC68020\))X
1448(with)X
1612(16)X
1714(MBytes)X
1989(of)X
2078(memory)X
2367(and)X
2505(two)X
2647(Hitachi)X
2904(892MByte)X
3267(disks)X
3452(\(15)X
3580(ms)X
3694(average)X
3966(seek)X
4130(time\))X
555 3393(behind)N
793(an)X
889(SMD-4)X
1149(controller.)X
1521(Frontends)X
1861(ran)X
1984(on)X
2084(an)X
2180(8MByte)X
2462(Sun)X
2606(3/260.)X
755 3516(In)N
844(order)X
1036(to)X
1120(measure)X
1410(performance)X
1839(on)X
1941(a)X
1999(machine)X
2293(of)X
2382(roughly)X
2653(equivalent)X
3009(processor)X
3339(power,)X
3582(we)X
3698(ran)X
3822(one)X
3959(set)X
4069(of)X
4157(tests)X
555 3606(on)N
666(a)X
733(standalone)X
1107(MC68030-based)X
1671(HP300)X
1923(\(33MHz)X
2225(MC68030\).)X
2646(The)X
2801(database)X
3108(was)X
3263(stored)X
3489(on)X
3599(a)X
3665(300MByte)X
4037(HP7959)X
555 3696(SCSI)N
744(disk)X
898(\(17)X
1026(ms)X
1139(average)X
1410(seek)X
1573(time\).)X
1802(Since)X
2000(this)X
2135(machine)X
2427(is)X
2500(not)X
2622(connected)X
2968(to)X
3050(a)X
3106(network,)X
3409(we)X
3523(ran)X
3646(local)X
3822(tests)X
3984(where)X
4201(the)X
555 3786(frontend)N
855(and)X
999(backend)X
1295(run)X
1430(on)X
1538(the)X
1664(same)X
1856(machine.)X
2195(We)X
2334(compare)X
2638(these)X
2830(measurements)X
3316(with)X
3485(Cattell's)X
3783(local)X
3966(Sun)X
4117(3/280)X
555 3876(numbers.)N
755 3999(Because)N
1051(the)X
1177(benchmark)X
1562(requires)X
1849(remote)X
2100(access,)X
2354(we)X
2476(ran)X
2607(another)X
2876(set)X
2993(of)X
3088(tests)X
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3365(a)X
3428(DECstation)X
3828(5000/200)X
4157(with)X
555 4089(32M)N
732(of)X
825(memory)X
1118(running)X
1393(Ultrix)X
1610(V4.0)X
1794(and)X
1936(a)X
1998(DEC)X
2184(1GByte)X
2459(RZ57)X
2666(SCSI)X
2859(disk.)X
3057(We)X
3194(compare)X
3496(the)X
3619(local)X
3800(performance)X
4232(of)X
555 4179(OO1)N
734(on)X
837(the)X
958(DECstation)X
1354(to)X
1439(its)X
1536(remote)X
1781(performance.)X
2250(For)X
2383(the)X
2503(remote)X
2748(case,)X
2929(we)X
3045(ran)X
3170(the)X
3290(frontend)X
3584(on)X
3686(a)X
3744(DECstation)X
4139(3100)X
555 4269(with)N
717(16)X
817(MBytes)X
1090(of)X
1177(main)X
1357(memory.)X
755 4392(The)N
900(databases)X
1228(tested)X
1435(in)X
1517([CATT91])X
1880(are)X
10 f
635 4515(g)N
1 f
755(INDEX,)X
1045(a)X
1101(highly-optimized)X
1672(access)X
1898(method)X
2158(package)X
2442(developed)X
2792(at)X
2870(Sun)X
3014(Microsystems.)X
10 f
635 4638(g)N
1 f
755(OODBMS,)X
1137(a)X
1193(beta)X
1347(release)X
1591(of)X
1678(a)X
1734(commercial)X
2133(object-oriented)X
2639(database)X
2936(management)X
3366(system.)X
10 f
635 4761(g)N
1 f
755(RDBMS,)X
1076(a)X
1133(UNIX-based)X
1565(commercial)X
1965(relational)X
2289(data)X
2444(manager)X
2742(at)X
2821(production)X
3189(release.)X
3474(The)X
3620(OO1)X
3797(implementation)X
755 4851(used)N
922(embedded)X
1272(SQL)X
1443(in)X
1525(C.)X
1638(Stored)X
1867(procedures)X
2240(were)X
2417(de\256ned)X
2673(to)X
2755(reduce)X
2990(client-server)X
3412(traf\256c.)X
755 4974(Table)N
974(two)X
1130(shows)X
1366(the)X
1500(measurements)X
1995(from)X
2187([CATT91])X
2566(and)X
2718(LIBTP)X
2976(for)X
3106(a)X
3178(local)X
3370(test)X
3517(on)X
3632(the)X
3765(MC680x0-based)X
555 5064(hardware.)N
915(All)X
1037(caches)X
1272(are)X
1391(cleared)X
1644(before)X
1870(each)X
2038(test.)X
2209(All)X
2331(times)X
2524(are)X
2643(in)X
2725(seconds.)X
755 5187(Table)N
960(two)X
1102(shows)X
1324(that)X
1466(LIBTP)X
1710(outperforms)X
2123(the)X
2242(commercial)X
2642(relational)X
2966(system,)X
3229(but)X
3352(is)X
3426(slower)X
3661(than)X
3820(OODBMS)X
4183(and)X
555 5277(INDEX.)N
872(Since)X
1077(the)X
1202(caches)X
1444(were)X
1628(cleared)X
1888(at)X
1973(the)X
2098(start)X
2263(of)X
2356(each)X
2530(test,)X
2687(disk)X
2846(throughput)X
3223(is)X
3302(critical)X
3551(in)X
3639(this)X
3780(test.)X
3957(The)X
4108(single)X
555 5367(SCSI)N
749(HP)X
877(drive)X
1068(used)X
1241(by)X
1347(LIBTP)X
1595(is)X
1674(approximately)X
2163(13%)X
2336(slower)X
2576(than)X
2739(the)X
2862(disks)X
3051(used)X
3223(in)X
3310([CATT91])X
3678(which)X
3899(accounts)X
4205(for)X
555 5457(part)N
700(of)X
787(the)X
905(difference.)X
755 5580(OODBMS)N
1118(and)X
1255(INDEX)X
1525(outperform)X
1906(LIBTP)X
2148(most)X
2323(dramatically)X
2744(on)X
2844(traversal.)X
3181(This)X
3343(is)X
3416(because)X
3691(we)X
3805(use)X
3932(index)X
4130(look-)X
555 5670(ups)N
689(to)X
774(\256nd)X
921(connections,)X
1347(whereas)X
1634(the)X
1755(other)X
1942(two)X
2084(systems)X
2359(use)X
2488(a)X
2546(link)X
2692(access)X
2920(method.)X
3222(The)X
3369(index)X
3569(requires)X
3850(us)X
3943(to)X
4027(examine)X
15 p
10 s 10 xH 0 xS 1 f
3 f
1 f
10 f
555 679(iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii)N
2 f
606 769(Measure)N
1 f
1019(INDEX)X
1389(OODBMS)X
1851(RDBMS)X
2250(LIBTP)X
10 f
555 771(iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii)N
555 787(iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii)N
1 f
595 869(Lookup)N
1114(5.4)X
1490(12.9)X
1950(27)X
2291(27.2)X
595 959(Traversal)N
1074(13)X
1530(9.8)X
1950(90)X
2291(47.3)X
595 1049(Insert)N
1114(7.4)X
1530(1.5)X
1950(22)X
2331(9.7)X
10 f
555 1059(iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii)N
555(c)X
999(c)Y
919(c)Y
839(c)Y
759(c)Y
959 1059(c)N
999(c)Y
919(c)Y
839(c)Y
759(c)Y
1329 1059(c)N
999(c)Y
919(c)Y
839(c)Y
759(c)Y
1791 1059(c)N
999(c)Y
919(c)Y
839(c)Y
759(c)Y
2190 1059(c)N
999(c)Y
919(c)Y
839(c)Y
759(c)Y
2512 1059(c)N
999(c)Y
919(c)Y
839(c)Y
759(c)Y
2618 679(i)N
2629(iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii)X
2 f
2829 769(Measure)N
3401(Cache)X
3726(Local)X
4028(Remote)X
1 f
10 f
2618 771(i)N
2629(iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii)X
2618 787(i)N
2629(iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii)X
1 f
2658 869(Lookup)N
3401(cold)X
3747(15.7)X
4078(20.6)X
3401 959(warm)N
3787(7.8)X
4078(12.4)X
10 f
2618 969(i)N
2629(iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii)X
1 f
2658 1059(Forward)N
2950(traversal)X
3401(cold)X
3747(28.4)X
4078(52.6)X
3401 1149(warm)N
3747(23.5)X
4078(47.4)X
10 f
2618 1159(i)N
2629(iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii)X
1 f
2658 1249(Backward)N
3004(traversal)X
3401(cold)X
3747(24.2)X
4078(47.4)X
3401 1339(warm)N
3747(24.3)X
4078(47.6)X
10 f
2618 1349(i)N
2629(iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii)X
1 f
2658 1439(Insert)N
3401(cold)X
3787(7.5)X
4078(10.3)X
3401 1529(warm)N
3787(6.7)X
4078(10.9)X
10 f
2618 1539(i)N
2629(iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii)X
2618(c)X
1479(c)Y
1399(c)Y
1319(c)Y
1239(c)Y
1159(c)Y
1079(c)Y
999(c)Y
919(c)Y
839(c)Y
759(c)Y
3341 1539(c)N
1479(c)Y
1399(c)Y
1319(c)Y
1239(c)Y
1159(c)Y
1079(c)Y
999(c)Y
919(c)Y
839(c)Y
759(c)Y
3666 1539(c)N
1479(c)Y
1399(c)Y
1319(c)Y
1239(c)Y
1159(c)Y
1079(c)Y
999(c)Y
919(c)Y
839(c)Y
759(c)Y
3968 1539(c)N
1479(c)Y
1399(c)Y
1319(c)Y
1239(c)Y
1159(c)Y
1079(c)Y
999(c)Y
919(c)Y
839(c)Y
759(c)Y
4309 1539(c)N
1479(c)Y
1399(c)Y
1319(c)Y
1239(c)Y
1159(c)Y
1079(c)Y
999(c)Y
919(c)Y
839(c)Y
759(c)Y
3 f
587 1785(Table)N
823(2:)X
931(Local)X
1163(MC680x0)X
1538(Performance)X
2026(of)X
2133(Several)X
587 1875(Systems)N
883(on)X
987(OO1.)X
2667 1785(Table)N
2909(3:)X
3023(Local)X
3260(vs.)X
3397(Remote)X
3707(Performance)X
4200(of)X
2667 1875(LIBTP)N
2926(on)X
3030(OO1.)X
1 f
10 f
555 1998(h)N
579(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)X
1 f
555 2274(two)N
696(disk)X
850(pages,)X
1074(but)X
1197(the)X
1316(links)X
1492(require)X
1741(only)X
1904(one,)X
2061(regardless)X
2408(of)X
2496(database)X
2794(size.)X
2980(Cattell)X
3214(reports)X
3458(that)X
3599(lookups)X
3873(using)X
4067(B-trees)X
555 2364(instead)N
808(of)X
901(links)X
1082(makes)X
1313(traversal)X
1616(take)X
1776(twice)X
1976(as)X
2069(long)X
2237(in)X
2325(INDEX.)X
2641(Adding)X
2907(a)X
2969(link)X
3119(access)X
3351(method)X
3617(to)X
3 f
3704(db)X
1 f
3792(\(3\))X
3911(or)X
4003(using)X
4201(the)X
555 2454(existing)N
828(hash)X
995(method)X
1255(would)X
1475(apparently)X
1834(be)X
1930(a)X
1986(good)X
2166(idea.)X
755 2577(Both)N
936(OODBMS)X
1304(and)X
1446(INDEX)X
1722(issue)X
1908 0.1944(coarser-granularity)AX
2545(locks)X
2739(than)X
2902(LIBTP.)X
3189(This)X
3356(limits)X
3562(concurrency)X
3985(for)X
4104(multi-)X
555 2667(user)N
711(applications,)X
1140(but)X
1264(helps)X
1455(single-user)X
1829(applications.)X
2278(In)X
2367(addition,)X
2671(the)X
2791(fact)X
2934(that)X
3076(LIBTP)X
3319(releases)X
3595(B-tree)X
3817(locks)X
4007(early)X
4189(is)X
4263(a)X
555 2757(drawback)N
896(in)X
986(OO1.)X
1210(Since)X
1416(there)X
1605(is)X
1686(no)X
1793(concurrency)X
2218(in)X
2307(the)X
2432(benchmark,)X
2836(high-concurrency)X
3430(strategies)X
3760(only)X
3929(show)X
4125(up)X
4232(as)X
555 2847(increased)N
882(locking)X
1145(overhead.)X
1503(Finally,)X
1772(the)X
1892(architecture)X
2294(of)X
2383(the)X
2503(LIBTP)X
2747(implementation)X
3271(was)X
3418(substantially)X
3844(different)X
4143(from)X
555 2937(that)N
702(of)X
796(either)X
1006(OODBMS)X
1375(or)X
1469(INDEX.)X
1786(Both)X
1968(of)X
2062(those)X
2258(systems)X
2538(do)X
2645(the)X
2770(searches)X
3070(in)X
3159(the)X
3284(user's)X
3503(address)X
3771(space,)X
3997(and)X
4139(issue)X
555 3027(requests)N
844(for)X
964(pages)X
1173(to)X
1260(the)X
1383(server)X
1605(process.)X
1911(Pages)X
2123(are)X
2247(cached)X
2496(in)X
2583(the)X
2706(client,)X
2929(and)X
3070(many)X
3273(queries)X
3530(can)X
3667(be)X
3768(satis\256ed)X
4055(without)X
555 3117(contacting)N
910(the)X
1029(server)X
1247(at)X
1326(all.)X
1467(LIBTP)X
1710(submits)X
1979(all)X
2080(the)X
2199(queries)X
2452(to)X
2535(the)X
2653(server)X
2870(process,)X
3151(and)X
3287(receives)X
3571(database)X
3868(records)X
4125(back;)X
555 3207(it)N
619(does)X
786(no)X
886(client)X
1084(caching.)X
755 3330(The)N
911(RDBMS)X
1221(architecture)X
1632(is)X
1716(much)X
1925(closer)X
2148(to)X
2241(that)X
2392(of)X
2490(LIBTP.)X
2783(A)X
2872(server)X
3100(process)X
3372(receives)X
3667(queries)X
3930(and)X
4076(returns)X
555 3420(results)N
786(to)X
870(a)X
928(client.)X
1168(The)X
1315(timing)X
1545(results)X
1776(in)X
1860(table)X
2038(two)X
2180(clearly)X
2421(show)X
2612(that)X
2754(the)X
2874(conventional)X
3309(database)X
3607(client/server)X
4025(model)X
4246(is)X
555 3510(expensive.)N
941(LIBTP)X
1188(outperforms)X
1605(the)X
1728(RDBMS)X
2032(on)X
2136(traversal)X
2437(and)X
2577(insertion.)X
2921(We)X
3057(speculate)X
3380(that)X
3524(this)X
3663(is)X
3740(due)X
3880(in)X
3966(part)X
4115(to)X
4201(the)X
555 3600(overhead)N
870(of)X
957(query)X
1160(parsing,)X
1436(optimization,)X
1880(and)X
2016(repeated)X
2309(interpretation)X
2761(of)X
2848(the)X
2966(plan)X
3124(tree)X
3265(in)X
3347(the)X
3465(RDBMS')X
3791(query)X
3994(executor.)X
755 3723(Table)N
962(three)X
1147(shows)X
1371(the)X
1492(differences)X
1873(between)X
2164(local)X
2343(and)X
2482(remote)X
2728(execution)X
3063(of)X
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555 3813(DECstation.)N
989(We)X
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555 4386(indices)N
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1974(id)X
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2059(order.)X
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3385 4853(5)N
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4885(.)Y
3476(This)X
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3 f
555 5161(6.)N
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1820(fsync)X
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1998(\(2\))X
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2426(\(2\))X
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555 5536(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)N
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1 f
727 5614(5)N
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1 f
555 630(stricter)N
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702(i.e.)X
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1 f
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3 f
555 2142(7.)N
655(Acknowledgements)X
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3 f
555 2721(8.)N
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1 f
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2 f
1134(CommUNIXations)X
1 f
1725(,)X
1765 0.2188(November/December)AX
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878(Bayer,)X
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2 f
3155(Acta)X
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1 f
3700(,)X
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2 f
1402(Proceedings)X
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1 f
3627(,)X
3667(October)X
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1109(4.4BSD)X
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2 f
2838(The)X
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1763(,)X
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1936(Proceedings)X
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1 f
3043(,)X
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972(Proceedings)X
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1 f
3408(,)X
3448(1985.)X
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2001(Proceedings)X
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1 f
2994(,)X
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2 f
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1 f
4279(,)X
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2 f
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1 f
1328(6\(2\);)X
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17 p
10 s 10 xH 0 xS 1 f
3 f
1 f
555 630([LEHM81])N
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1 f
1308(,)X
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2 f
1398(Proceedings)X
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1 f
3449(,)X
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2 f
1242(Proceedings)X
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1 f
3598(,)X
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