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<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt">Hi All,<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt">Need suggestion.<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt">we are seeing delay in TCP query for 4sec in some set of caching servers (Its acting as a forwarder).<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt">The query is having bunch of NS (61 Name server) so its truncating to TCP. Only the delay is happening on particular set of forwarders.
<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt">OS<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt">Linux 2.6.32-642.el6.x86_64<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt">I got this option from one site to set the “net.ipv4.tcp_limit_output_bytes” to 128K (</span><u><span style="font-size:14.0pt;font-family:Helvetica;color:blue"><a href="https://lwn.net/Articles/507065/)">https://lwn.net/Articles/507065/)</a><o:p></o:p></span></u></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt">The default value of this limit is 128KB; it could be set lower on systems where latency is the primary concern.<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt">/proc/sys/net/ipv4/tcp_limit_output_bytes<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt">- net.ipv4.tcp_limit_output_bytes = 262144<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:15.0pt">+ net.ipv4.tcp_limit_output_bytes = 131072</span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:15.0pt">Need advice on this.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Times New Roman"">Thanks<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Times New Roman"">Karthikeyan.S<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Times New Roman""> <o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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