<!--$Id: event.so,v 1.2 2007/05/14 16:03:56 bostic Exp $--> <!--Copyright (c) 1997,2008 Oracle. All rights reserved.--> <!--See the file LICENSE for redistribution information.--> <html> <head> <title>Berkeley DB Reference Guide: Release 4.6: replication events</title> <meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> <meta name="keywords" content="embedded,database,programmatic,toolkit,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++"> </head> <body bgcolor=white> <table width="100%"><tr valign=top> <td><b><dl><dt>Berkeley DB Reference Guide:<dd>Upgrading Berkeley DB Applications</dl></b></td> <td align=right><a href="../upgrade.4.6/memp_fset.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../upgrade.4.6/full_election.html"><img src="../../images/next.gif" alt="Next"></a> </td></tr></table> <p align=center><b>Release 4.6: replication events</b></p> <p>It is now guaranteed the <a href="../../api_c/env_event_notify.html#DB_EVENT_REP_STARTUPDONE">DB_EVENT_REP_STARTUPDONE</a> event will be presented to the application after the corresponding <a href="../../api_c/env_event_notify.html#DB_EVENT_REP_NEWMASTER">DB_EVENT_REP_NEWMASTER</a> event, even in the face of extreme thread-scheduling anomalies. (In previous releases, if the thread processing the NEWMASTER message was starved, and STARTUPDONE occurred soon after, the order might have been reversed.)</p> <p>In addition, the <a href="../../api_c/env_event_notify.html#DB_EVENT_REP_NEWMASTER">DB_EVENT_REP_NEWMASTER</a> event is now presented to all types of replication applications: users of either the Replication Framework or the Base Replication API. In both cases, the <a href="../../api_c/env_event_notify.html#DB_EVENT_REP_NEWMASTER">DB_EVENT_REP_NEWMASTER</a> event always means that a site other than the local environment has become master.</p> <p>The <b>envid</b> parameter to <a href="../../api_c/rep_message.html">DB_ENV->rep_process_message</a> has been changed to be of type "int" rather than "int *", and the environment ID of a new master is presented to the application along with the <a href="../../api_c/env_event_notify.html#DB_EVENT_REP_NEWMASTER">DB_EVENT_REP_NEWMASTER</a> event. Replication applications should be modified to use the <a href="../../api_c/env_event_notify.html#DB_EVENT_REP_NEWMASTER">DB_EVENT_REP_NEWMASTER</a> event to determine the ID of the new master.</p> <p>The <b>envid</b> parameter has been removed from the <a href="../../api_c/rep_elect.html">DB_ENV->rep_elect</a> method and a new event type has been added. The <a href="../../api_c/env_event_notify.html#DB_EVENT_REP_ELECTED">DB_EVENT_REP_ELECTED</a> event is presented to the application at the site which wins an election. In the Berkeley DB 4.6 release, the normal result of a successful election is either the <a href="../../api_c/env_event_notify.html#DB_EVENT_REP_NEWMASTER">DB_EVENT_REP_NEWMASTER</a> event (with the winner's environment ID), or the <a href="../../api_c/env_event_notify.html#DB_EVENT_REP_ELECTED">DB_EVENT_REP_ELECTED</a> event. Only one of the two events will ever be delivered.</p> <p>The DB_REP_NEWMASTER return code has been removed from the <a href="../../api_c/rep_message.html">DB_ENV->rep_process_message</a> method. Replication applications should be modified to use the <a href="../../api_c/env_event_notify.html#DB_EVENT_REP_NEWMASTER">DB_EVENT_REP_NEWMASTER</a> and <a href="../../api_c/env_event_notify.html#DB_EVENT_REP_ELECTED">DB_EVENT_REP_ELECTED</a> events to determine the existence of a new master.</p> <table width="100%"><tr><td><br></td><td align=right><a href="../upgrade.4.6/memp_fset.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../upgrade.4.6/full_election.html"><img src="../../images/next.gif" alt="Next"></a> </td></tr></table> <p><font size=1>Copyright (c) 1996,2008 Oracle. All rights reserved.</font> </body> </html>