Sindbad~EG File Manager
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<p>Library Version 18.1.40</p>
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<th colspan="3" align="center">Multiversion Concurrency Control (MVCC)
for Replication Clients</th>
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<h2 class="title" style="clear: both"><a id="mvcc_rep_clients"></a>Multiversion Concurrency Control (MVCC)
for Replication Clients</h2>
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<p>
Multiversion Concurrency Control (MVCC) is a Berkeley DB feature that offers repeatable
reads, but with a different performance tradeoff than default Berkeley DB
Transactional Data Store (TDS) behavior. MVCC makes extra copies of database pages
when performing write operations. This is known as the copy-on-write protocol. These
additional copies of database pages enable read operations to avoid locking while still
remaining repeatable.
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MVCC was originally implemented for replication masters and has been extended
to replication clients. MVCC is desirable on replication clients because some
applications are read-intensive on client sites and it is useful to optimize
read operation performance on these sites.
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Sindbad File Manager Version 1.0, Coded By Sindbad EG ~ The Terrorists