eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi<!DOCTYPE modulesynopsis SYSTEM "/style/modulesynopsis.dtd">
eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi<?xml-stylesheet type="text/xsl" href="/style/manual.en.xsl"?>
eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi<!-- $LastChangedRevision$ -->
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eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi this work for additional information regarding copyright ownership.
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eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi the License. You may obtain a copy of the License at
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eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi distributed under the License is distributed on an "AS IS" BASIS,
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eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi<modulesynopsis metafile="mod_lbmethod_bybusyness.xml.meta">
eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi<description>Pending Request Counting load balancer scheduler algorithm for <module
eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi<compatibility>Split off from <module>mod_proxy_balancer</module> in 2.3</compatibility>
a357a8bf5e65ac967c6faea297fbd6d1f8373c05rbowen<p>This module does not provide any configuration directives of its own.
a357a8bf5e65ac967c6faea297fbd6d1f8373c05rbowenIt requires the services of <module>mod_proxy_balancer</module>, and
ae697e78eeadf77eb17e652d22442b3bb5c3b3fdrbowenprovides the <code>bybusyness</code> load balancing method.</p>
eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi<seealso><module>mod_proxy_balancer</module></seealso>
eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi <p>Enabled via <code>lbmethod=bybusyness</code>, this scheduler keeps
a6f5eeb5143ca0a2857af609084f6a325f437ac4jim track of how many requests each worker is currently assigned at present. A new
eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi request is automatically assigned to the worker with the lowest
eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi number of active requests. This is useful in the case of workers
eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi that queue incoming requests independently of Apache, to ensure that
eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi queue length stays even and a request is always given to the worker
a6f5eeb5143ca0a2857af609084f6a325f437ac4jim most likely to service it the fastest and reduce latency.</p>
eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi <p>In the case of multiple least-busy workers, the statistics (and
eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi weightings) used by the Request Counting method are used to break the
eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi tie. Over time, the distribution of work will come to resemble that
a6f5eeb5143ca0a2857af609084f6a325f437ac4jim characteristic of <code>byrequests</code> (as implemented
eea3f46e1c885fa5107e376c58b39338cb4bfb09takashi</modulesynopsis>