How to count dropped connections

[Noam Rathaus]

Amos,

What are you trying to count? I hope I understood you correctly, you want to
know how many HTTP requests are being handled, against those that couldn't
be handled due to lack of connections.

netstat is a very bad counting devices, unless you are counting packets.

If you want to count "requests" I would count incoming connection requests
(SYN) vs apache log of requests

The incoming connections should be counted using tcpdump or similar

while apache log should be easily achievable by grep

On Tue, Jun 9, 2009 at 1:44 PM, Amos Shapira <amos.shapira at gmail.com> wrote:

> Hello,
>
> We are running a cluster of web servers of various functions on top of
> CentOS 5, and would like to know whether and how many requests we
> might be dropping because of insufficient provisioning. The cluster
> could be hit by a a few millions requests per day soon and we'd like
> the stats to be there both now (in case we miss something obvious) and
> when the crowd comes charging.
>
> Googl'ing around for explanations of "netstat -s" and the files under
> /proc/net didn't come up with anything which looks like the definite
> answer, except maybe "packets pruned from receive queue because of
> socket buffer overrun", but I'm not sure what it counts.
>
> Does anyone know how to get the stats I want?
>
> Thanks,
>
> --Amos
>
> _______________________________________________
> Linux-il mailing list
> Linux-il at cs.huji.ac.il
> http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.cs.huji.ac.il/pipermail/linux-il/attachments/20090609/dd4f53ac/attachment.html>