1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>xprt_adjust_cwnd</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="Linux Networking and Network Devices APIs"><link rel="up" href="ch01s05.html" title="SUN RPC subsystem"><link rel="prev" href="API-xprt-release-rqst-cong.html" title="xprt_release_rqst_cong"><link rel="next" href="API-xprt-wake-pending-tasks.html" title="xprt_wake_pending_tasks"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><span class="phrase">xprt_adjust_cwnd</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-xprt-release-rqst-cong.html">Prev</a>&#160;</td><th width="60%" align="center">SUN RPC subsystem</th><td width="20%" align="right">&#160;<a accesskey="n" href="API-xprt-wake-pending-tasks.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-xprt-adjust-cwnd"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>xprt_adjust_cwnd &#8212; 
2     adjust transport congestion window
3 </p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">void <b class="fsfunc">xprt_adjust_cwnd </b>(</code></td><td>struct rpc_xprt * <var class="pdparam">xprt</var>, </td></tr><tr><td>&#160;</td><td>struct rpc_task * <var class="pdparam">task</var>, </td></tr><tr><td>&#160;</td><td>int <var class="pdparam">result</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1097144964"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>xprt</code></em></span></dt><dd><p>
4     pointer to xprt
5    </p></dd><dt><span class="term"><em class="parameter"><code>task</code></em></span></dt><dd><p>
6     recently completed RPC request used to adjust window
7    </p></dd><dt><span class="term"><em class="parameter"><code>result</code></em></span></dt><dd><p>
8     result code of completed RPC request
9    </p></dd></dl></div></div><div class="refsect1"><a name="idp1097148668"></a><h2>Description</h2><p>
10   The transport code maintains an estimate on the maximum number of out-
11   standing RPC requests, using a smoothed version of the congestion
12   avoidance implemented in 44BSD. This is basically the Van Jacobson
13</p></div><div class="refsect1"><a name="idp1097149484"></a><h2>congestion algorithm</h2><p>
14   If a retransmit occurs, the congestion window is
15   halved; otherwise, it is incremented by 1/cwnd when
16   </p><p>
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18   -	a reply is received and
19   -	a full number of requests are outstanding and
20   -	the congestion window hasn't been updated recently.
21</p></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="API-xprt-release-rqst-cong.html">Prev</a>&#160;</td><td width="20%" align="center"><a accesskey="u" href="ch01s05.html">Up</a></td><td width="40%" align="right">&#160;<a accesskey="n" href="API-xprt-wake-pending-tasks.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">xprt_release_rqst_cong</span>&#160;</td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top">&#160;<span class="phrase">xprt_wake_pending_tasks</span></td></tr></table></div></body></html>
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