ibm-information-center/dist/eclipse/plugins/i5OS.ic.apiref_5.4.0.1/conPerformance.htm

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<h1 class="topictitle1">Performance considerations</h1>
<div><p>The retrieve APIs allow you to control the performance cost for
information you retrieve.</p>
<p>The format specified for any API influences the performance cost of the
API. In general, when more information is returned, the performance is slower.</p>
<p>Some list APIs, such as list jobs, list spooled files, and list objects,
generate the list with minimal cost. This is why these formats do not retrieve
very much information. Some of the APIs, such as list record formats and list
fields, have only one format, because there is no additional performance cost
to supply the complete information.</p>
<p>The retrieve APIs, such as retrieve member description and retrieve spooled
file attributes, have formats that are generally ordered from fastest performance
to slowest performance. That is, the lower numbered formats run faster but
retrieve less information, and the higher numbered formats run slower but
retrieve more information. One exception is the Retrieve Job Information (QUSRJOBI)
API where the order of the formats does not have anything to do with performance
characteristics. For more information about the performance characteristics
for the QUSRJOBI API formats, see the Retrieve Job Information (QUSRJOBI)
API in Work Management APIs.</p>
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<div class="parentlink"><strong>Parent topic:</strong> <a href="concept.htm" title="Describes the underlying concepts that you need to understand to work effectively with APIs. Among the concepts covered are basic concepts, programming considerations, and terminology.">API concepts</a></div>
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<div class="relref"><strong>Related reference</strong><br />
<div><a href="../apis/qusrjobi.htm">Retrieve Job Information (QUSRJOBI) API</a></div>
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