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<title>Berkeley DB Reference Guide: Bulk transfer</title>
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<td><b><dl><dt>Berkeley DB Reference Guide:<dd>Berkeley DB Replication</dl></b></td>
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<p align=center><b>Bulk transfer</b></p>
<p>Sites in a replication group may be configured to use bulk transfer by
calling the <a href="../../api_c/rep_config.html">DB_ENV-&gt;rep_set_config</a> method with the <a href="../../api_c/rep_config.html#DB_REP_CONF_BULK">DB_REP_CONF_BULK</a>
flag.  When configured for bulk transfer, sites will accumulate records
in a buffer and transfer them to another site in a single network
transfer.  Configuring bulk transfer makes sense for master sites, of
course.  Additionally, applications using client-to-client
synchronization may find it helpful to configure bulk transfer for
client sites as well.</p>
<p>When a master is generating new log records, or any information request
is made of a master, and bulk transfer has been configured, records will
accumulate in a bulk buffer.  The bulk buffer will be sent to the client
if either the buffer is full or if a permanent record (for example, a
transaction commit or checkpoint record) is queued for the client.</p>
<p>When a client is responding to another client's request for information,
and bulk transfer has been configured, records will accumulate in a bulk
buffer.  The bulk buffer will be sent to the client when the buffer is
full or when the client's request has been satisfied; no particular type
of record will cause the buffer to be sent.</p>
<p>The size of the bulk buffer itself is internally determined and cannot
be configured.  However, the overall size of a transfer may be limited
using the <a href="../../api_c/rep_limit.html">DB_ENV-&gt;rep_set_limit</a> method.</p>
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