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<h1 class="topictitle1">Java garbage collection performance considerations</h1>
<div><p>Garbage collection on the iSeries™ Java™ virtual machine operates in a continuous
asynchronous mode. The garbage collection-initial size (GCHINL) parameter
on the Run Java (RUNJVA) command may affect application performance. </p>
<p>The GCHINL parameter specifies the amount of new object space that is allowed
between garbage collections. A small value may cause too much garbage collection
overhead. A large value may limit garbage collection and cause out of memory
errors. However, for most applications, the default values should be correct.</p>
<p>Garbage collection determines that an object is no longer needed by evaluating
whether there are any valid references to that object.</p>
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<div class="parentlink"><strong>Parent topic:</strong> <a href="gc.htm" title="Garbage collection is the process of freeing storage that is used by objects that are no longer referred to by a program. With garbage collection, programmers no longer have to write error prone code to explicitly &#34;free&#34; or &#34;delete&#34; their objects. This code frequently results in &#34;memory leak&#34; program errors. The garbage collector automatically detects an object or group of objects that the user program can no longer reach. It does this because there are no references to that object in any program structure. Once the object has been collected, you can allocate the space for other uses.">Java garbage collection</a></div>
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<div class="relconcepts"><strong>Related concepts</strong><br />
<div><a href="advgc.htm" title="The IBM Developer Kit for Java implements an advanced garbage collector algorithm. This algorithm allows the discovery and collection of unreachable objects without significant pauses in the operation of the Java program. A concurrent collector cooperatively discovers the references to objects under the running threads, instead of a single thread.">IBM Developer Kit for Java advanced garbage collection</a></div>
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