1<!--$Id: bulk.so,v 1.4 2006/07/14 23:04:42 alanb Exp $--> 2<!--Copyright (c) 1997,2008 Oracle. All rights reserved.--> 3<!--See the file LICENSE for redistribution information.--> 4<html> 5<head> 6<title>Berkeley DB Reference Guide: Bulk transfer</title> 7<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> 8<meta name="keywords" content="embedded,database,programmatic,toolkit,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++"> 9</head> 10<body bgcolor=white> 11<table width="100%"><tr valign=top> 12<td><b><dl><dt>Berkeley DB Reference Guide:<dd>Berkeley DB Replication</dl></b></td> 13<td align=right><a href="/rep/init.html"><img src="/images/prev.gif" alt="Prev"></a><a href="/toc.html"><img src="/images/ref.gif" alt="Ref"></a><a href="/rep/trans.html"><img src="/images/next.gif" alt="Next"></a> 14</td></tr></table> 15<p align=center><b>Bulk transfer</b></p> 16<p>Sites in a replication group may be configured to use bulk transfer by 17calling the <a href="/api_c/rep_config.html">DB_ENV->rep_set_config</a> method with the <a href="/api_c/rep_config.html#DB_REP_CONF_BULK">DB_REP_CONF_BULK</a> 18flag. When configured for bulk transfer, sites will accumulate records 19in a buffer and transfer them to another site in a single network 20transfer. Configuring bulk transfer makes sense for master sites, of 21course. Additionally, applications using client-to-client 22synchronization may find it helpful to configure bulk transfer for 23client sites as well.</p> 24<p>When a master is generating new log records, or any information request 25is made of a master, and bulk transfer has been configured, records will 26accumulate in a bulk buffer. The bulk buffer will be sent to the client 27if either the buffer is full or if a permanent record (for example, a 28transaction commit or checkpoint record) is queued for the client.</p> 29<p>When a client is responding to another client's request for information, 30and bulk transfer has been configured, records will accumulate in a bulk 31buffer. The bulk buffer will be sent to the client when the buffer is 32full or when the client's request has been satisfied; no particular type 33of record will cause the buffer to be sent.</p> 34<p>The size of the bulk buffer itself is internally determined and cannot 35be configured. However, the overall size of a transfer may be limited 36using the <a href="/api_c/rep_limit.html">DB_ENV->rep_set_limit</a> method.</p> 37<table width="100%"><tr><td><br></td><td align=right><a href="/rep/init.html"><img src="/images/prev.gif" alt="Prev"></a><a href="/toc.html"><img src="/images/ref.gif" alt="Ref"></a><a href="/rep/trans.html"><img src="/images/next.gif" alt="Next"></a> 38</td></tr></table> 39<p><font size=1>Copyright (c) 1996,2008 Oracle. All rights reserved.</font> 40</body> 41</html> 42
