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diff --git a/static/freebsd/man4/cc_vegas.4 3.html b/static/freebsd/man4/cc_vegas.4 3.html deleted file mode 100644 index 8660bca9..00000000 --- a/static/freebsd/man4/cc_vegas.4 3.html +++ /dev/null @@ -1,111 +0,0 @@ -<table class="head"> - <tr> - <td class="head-ltitle">CC_VEGAS(4)</td> - <td class="head-vol">Device Drivers Manual</td> - <td class="head-rtitle">CC_VEGAS(4)</td> - </tr> -</table> -<div class="manual-text"> -<section class="Sh"> -<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> -<p class="Pp"><code class="Nm">cc_vegas</code> — <span class="Nd">Vegas - Congestion Control Algorithm</span></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> -<p class="Pp">The Vegas congestion control algorithm uses what the authors term - the actual and expected transmission rates to determine whether there is - congestion along the network path i.e.</p> -<ul class="Bl-item Bd-indent"> - <li>actual rate = (total data sent in a RTT) / RTT</li> - <li>expected rate = cwnd / RTTmin</li> - <li>diff = expected - actual</li> -</ul> -<p class="Pp">where RTT is the measured instantaneous round trip time and RTTmin - is the smallest round trip time observed during the connection.</p> -<p class="Pp">The algorithm aims to keep diff between two parameters alpha and - beta, such that:</p> -<ul class="Bl-item Bd-indent"> - <li>alpha < diff < beta</li> -</ul> -<p class="Pp">If diff > beta, congestion is inferred and cwnd is decremented - by one packet (or the maximum TCP segment size). If diff < alpha, then - cwnd is incremented by one packet. Alpha and beta govern the amount of - buffering along the path.</p> -<p class="Pp">The implementation was done in a clean-room fashion, and is based - on the paper referenced in the <a class="Sx" href="#SEE_ALSO">SEE ALSO</a> - section below.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="IMPLEMENTATION_NOTES"><a class="permalink" href="#IMPLEMENTATION_NOTES">IMPLEMENTATION - NOTES</a></h1> -<p class="Pp">The time from the transmission of a marked packet until the - receipt of an acknowledgement for that packet is measured once per RTT. This - implementation does not implement Brakmo's and Peterson's original duplicate - ACK policy since clock ticks in today's machines are not as coarse as they - were (i.e. 500ms) when Vegas was originally designed. Note that modern TCP - recovery processes such as fast retransmit and SACK are enabled by default - in the TCP stack.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="MIB_Variables"><a class="permalink" href="#MIB_Variables">MIB - Variables</a></h1> -<p class="Pp">The algorithm exposes the following tunable variables in the - <var class="Va">net.inet.tcp.cc.vegas</var> branch of the - <a class="Xr">sysctl(3)</a> MIB:</p> -<dl class="Bl-tag"> - <dt id="alpha"><var class="Va">alpha</var></dt> - <dd>Query or set the Vegas alpha parameter as a number of buffers on the path. - When setting alpha, the value must satisfy: 0 < alpha < beta. - Default is 1.</dd> - <dt id="beta"><var class="Va">beta</var></dt> - <dd>Query or set the Vegas beta parameter as a number of buffers on the path. - When setting beta, the value must satisfy: 0 < alpha < beta. Default - is 3.</dd> -</dl> -</section> -<section class="Sh"> -<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE - ALSO</a></h1> -<p class="Pp"><a class="Xr">cc_cdg(4)</a>, <a class="Xr">cc_chd(4)</a>, - <a class="Xr">cc_cubic(4)</a>, <a class="Xr">cc_dctcp(4)</a>, - <a class="Xr">cc_hd(4)</a>, <a class="Xr">cc_htcp(4)</a>, - <a class="Xr">cc_newreno(4)</a>, <a class="Xr">h_ertt(4)</a>, - <a class="Xr">mod_cc(4)</a>, <a class="Xr">tcp(4)</a>, - <a class="Xr">khelp(9)</a>, <a class="Xr">mod_cc(9)</a></p> -<p class="Pp"><cite class="Rs"><span class="RsA">L. S. Brakmo</span> and - <span class="RsA">L. L. Peterson</span>, <span class="RsT">TCP Vegas: end to - end congestion avoidance on a global internet</span>, <i class="RsJ">IEEE J. - Sel. Areas Commun.</i>, <span class="RsN">8</span>, - <span class="RsV">13</span>, <span class="RsP">1465-1480</span>, - <span class="RsD">October 1995</span>.</cite></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="ACKNOWLEDGEMENTS"><a class="permalink" href="#ACKNOWLEDGEMENTS">ACKNOWLEDGEMENTS</a></h1> -<p class="Pp">Development and testing of this software were made possible in - part by grants from the FreeBSD Foundation and Cisco University Research - Program Fund at Community Foundation Silicon Valley.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> -<p class="Pp">The <code class="Nm">cc_vegas</code> congestion control module - first appeared in <span class="Ux">FreeBSD 9.0</span>.</p> -<p class="Pp">The module was first released in 2010 by David Hayes whilst - working on the NewTCP research project at Swinburne University of - Technology's Centre for Advanced Internet Architectures, Melbourne, - Australia. More details are available at:</p> -<p class="Pp">http://caia.swin.edu.au/urp/newtcp/</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h1> -<p class="Pp">The <code class="Nm">cc_vegas</code> congestion control module and - this manual page were written by <span class="An">David Hayes</span> - <<a class="Mt" href="mailto:david.hayes@ieee.org">david.hayes@ieee.org</a>>.</p> -</section> -</div> -<table class="foot"> - <tr> - <td class="foot-date">May 13, 2021</td> - <td class="foot-os">FreeBSD 15.0</td> - </tr> -</table> |