nginx/Win2008R2 stops responding after few sessions

[Kurien Mathew]

Hello,

I am running nginx 1.0.10 (native build) on Windows 2008 R2 with 2 worker
processes.

I am serving a static file (chunk.ts 375000 bytes) to a httperf client
running on CentOS 6. The client executes 4 concurrent connections and sends
out 96 requests on each. The client has a response timeout set at 2
seconds. In the first execution of the client all 4 sessions succeed but in
the second execution 2 sessions timeout due the lack of a response. In the
third & fourth execution all sessions timeout.

I have some debug data available at
http://www.mediafire.com/?yct3s1720flgvz3. The archive contains

chunk.ts - the static file being served
error.log - nginx error log (debug level)
httperfout.txt - output of httperf executions
NetworkMonitor.cap - Packet capture from nginx server (using Network
Monitor)
nginx.conf - nginx conf used

The network capture shows TCP ACK for the request but no response from
nginx during 2 seconds. The nginx log shows 6 successfult sessions but
nothing much after that. If the server is restarted a few sessions would
succeed before it stops responding.

And importantly, there is no problem when the number of worker processes is
set to 1.

Would you have any additional clues about what is going wrong?

Thanks
Kurien
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.nginx.org/pipermail/nginx/attachments/20111209/8ef42b50/attachment.html>