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<TITLE>Re: Varnish child killed</TITLE>
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<FONT SIZE="4"><FONT FACE="Calibri, Verdana, Helvetica, Arial"><SPAN STYLE='font-size:11pt'>HI Thiago !<BR>
<BR>
Thank you a lot for your very interesting comment !<BR>
<BR>
In fact I get the same limitation with a 8GB memory server.<BR>
<BR>
Please correct me if I’m wrong :<BR>
My system has only 8GB of memory. Thus I can assume that the kernel should have stared to write dirty </SPAN></FONT><FONT FACE="Tahoma, Verdana, Helvetica, Arial"><SPAN STYLE='font-size:10pt'>mmap'ed pages longer in advance than your server does.<BR>
<BR>
But the very high loads I’ve seen are only occuring once the cache became close to 20GB+.<BR>
Why is that ? I still don’t understand this 20GB+ limitation. <BR>
</SPAN></FONT><FONT FACE="Calibri, Verdana, Helvetica, Arial"><SPAN STYLE='font-size:11pt'><BR>
I addition of the vmstat and ps that I collect regularly, I will add an iostat to watch the disk activity.<BR>
<BR>
<BR>
Jef<BR>
<BR>
<BR>
Le 27/04/11 00:26, « Thiago Figueiro » a écrit :<BR>
<BR>
</SPAN></FONT></FONT><BLOCKQUOTE><FONT SIZE="4"><FONT FACE="Consolas, Courier New, Courier"><SPAN STYLE='font-size:10pt'>From: Jean-Francois Laurens<BR>
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> Hi there,<BR>
<BR>
> Apr 20 21:48:43 server-01-39 varnishd[21087]: Child (5372) not responding <BR>
> to CLI, killing it.<BR>
<BR>
Hi! I'm a bit late to the discussion (happy Easter everyone!) but we came across this issue on Linux earlier this year.<BR>
<BR>
You didn't send charts for your disk IO but I'm betting it looks busy. If this is so, it may be the kernel pre-empting writing of dirty mmap pages to disk.<BR>
<BR>
I investigated the issue at the time and found that on the RHEL 5 vanilla kernel the Varnish child was being blocked by kernel IO. This caused the parent pings to time-out:<BR>
<BR>
<a href="http://microrants.blogspot.com/2010/07/varnish-and-linux-io-bottleneck.html">http://microrants.blogspot.com/2010/07/varnish-and-linux-io-bottleneck.html</a><BR>
<BR>
<BR>
TL;DR: <BR>
echo 0 > /proc/sys/vm/flush_mmap_pages<BR>
<BR>
<BR>
<BR>
Good luck,<BR>
Thiago.<BR>
<BR>
<BR>
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</SPAN></FONT></FONT><FONT COLOR="#808080"><FONT FACE="Arial"><SPAN STYLE='font-size:9pt'>Jean-Francois Laurens<BR>
</SPAN><FONT SIZE="4"><SPAN STYLE='font-size:10pt'>Ingénieur Système Unix<BR>
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