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<title>Berkeley DB: DbEnv.set_tas_spins</title>
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<h1>DbEnv.set_tas_spins</h1>
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<h3><pre>
import com.sleepycat.db.*;
<p>
int
DbEnv.set_tas_spins(u_int32_t tas_spins);
throws DbException;
</pre></h3>
<h1>Description</h1>
<p>Specify that test-and-set mutexes should spin <b>tas_spins</b> times
without blocking. The value defaults to 1 on uniprocessor systems and
to 50 times the number of processors on multiprocessor systems.
<p>The DbEnv.set_tas_spins method configures operations performed using the specified
<a href="../api_java/env_class.html">DbEnv</a> handle, not all operations performed on the underlying
database environment.
<p>The DbEnv.set_tas_spins interface may be called at any time during the life of
the application.
<p>The DbEnv.set_tas_spins method throws an exception that encapsulates a non-zero error value on
failure.
<p>The database environment's test-and-set spin count may also be set using the environment's
<b>DB_CONFIG</b> file. The syntax of the entry in that file is a
single line with the string "set_tas_spins", one or more whitespace characters,
and the number of spins. Because the <b>DB_CONFIG</b> file is read when the database
environment is opened, it will silently overrule configuration done
before that time.
<h1>Errors</h1>
<p>The DbEnv.set_tas_spins method may fail and throw an exception encapsulating a non-zero error for the following conditions:
<p><dl compact>
<p><dt>EINVAL<dd>An invalid flag value or parameter was specified.
</dl>
<p>The DbEnv.set_tas_spins method may fail and throw an exception for errors specified for other Berkeley DB and C library or system methods.
If a catastrophic error has occurred, the DbEnv.set_tas_spins method may fail and
throw a <a href="../api_java/runrec_class.html">DbRunRecoveryException</a>,
in which case all subsequent Berkeley DB calls will fail in the same way.
<h1>Class</h1>
<a href="../api_java/env_class.html">DbEnv</a>
<h1>See Also</h1>
<a href="../api_java/env_list.html">Database Environments and Related Methods</a>
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