Re: Error from polyclient

On Thu, 2006-04-13 at 17:23 -0700, Balu wrote:

> I am running the polygrpah test on squid. My setup
> with NO-PROXY runs just fine. 
> 
> But when I run with proxy I am getting the following
> error, though the test seems to complete with out
> stoping in the middle.
> ======================================================
> 002.46| i-warm    376   3.00   1989   0.00   0  188
> 002.54| i-warm    387   2.20   2269   0.00   0  194
> 002.63| i-warm    407   4.00   2023   0.00   0  195
> 002.71| i-warm    422   3.00   2644   0.00   0  194
> 002.79| i-warm    430   1.60   2299   0.00   0  193
> 002.88| i-warm    445   3.00   1890   0.00   0  194
> 002.96| i-warm    467   4.40   2244   0.00   0  198
> 003.04| i-warm    478   2.20   3224   0.00   0  196
.. 
> 003.25| Connection.cc:485: error: 8/8 (s110)
> Connection timed out
> 003.25| error: raw write after connect failed
> 003.25| connection to 192.10.10.43:3128 failed after 0
> reads, 0 writes, 1 xacts
> ==========================================
>  
> Please do let me know, If need to tune parameters.
> I am running squid on red hat enterprise version.
> Polygraph on FC4.

Many conditions can cause a connection timeout error. Your load levels
seem to be relatively low so I would check the following, in the listed
order:

1. Are there any I/O errors causing as packet loss on the network
interfaces involved in request handling? If yes, check for duplex
conflicts, bad cables, and other networking problems. Netstat -i reports
relevant interface I/O statistics on FreeBSD and perhaps Linux.

2. Does the Squid box report lost/aborted connections due to TCP listen
queue overflows? If yes, increase the queue length. Netstat -s reports
relevant low-level TCP statistics on FreeBSD and, I think, Linux.

3. Does Squid have enough file descriptors to work with? Make sure Squid
has at least 600 (given ~200 concurrent connections reported on one side
of the test above). Check Squid's cache.log for information on the
number of available file descriptors.

4. Any other errors on the Squid box? Check system message log,
cache.log, and netstat -s.

5. Any other errors on Polygraph box(es)? Check system message log,
Polygraph logs on both sides (with verbosity level 10), and netstat -s.

HTH,

Alex.