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<head><title>Commit Frequency </title>
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<h1>Commit Frequency</h1>
<p>Commit time has a major influence on all db4o operations.
Commit is generally a slow operation as it requires physical disk access. The
following example shows how the frequency of commits affects the delete
performance:</p>
<p MadCap:conditions="Global.Primary:java" />
<p>The following initial setup is used:</p>
<p MadCap:conditions="Global.Primary:java" />
<p>Delete procedures are as follows:</p>
<p MadCap:conditions="Global.Primary:java" />
<p MadCap:conditions="Global.Primary:java" />
<p>Item class used in this example has depth = 3:</p>
<p MadCap:conditions="Global.Primary:java" />
<p>The results on the test computer are:</p>
<p><i>Delete test with
different commit frequency</i>
</p>
<p><i>Test delete all:</i>
</p>
<p><i>Store 30000
objects: 2432ms</i>
</p>
<p><i>Deleted all
objects: 3731ms</i>
</p>
<p><i>Test delete all
with commit after each 1000 objects:</i>
</p>
<p><i>Store 30000
objects: 2103ms</i>
</p>
<p><i>Deleted all objects: 8615ms</i>
</p>
<p>You can see that the time required
for deletion increased with the amount of commits. To improve the performance
commit frequency should be kept relatively low,
in the same time it must ensure the integrity of the logical
transactions. </p>
<p MadCap:conditions="Primary.Online">Download example code:</p>
<p MadCap:conditions="Primary.Online">
<MadCap:conditionalText MadCap:conditions="Primary..NET,Primary.c#,Primary.All languages"><a href="../performancecs.zip">c# </a>
</MadCap:conditionalText>
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