Re: apache process locks at 100% cpu usage

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



And how about this: after benchmarking apache with ab -c 100 -n 10000 an apache process is left in the process list for a while with <defunct> appended - it disappears after a minute or so.

If I benchmark the server from two different machines with two different requests, apache locks up, the benchmarks time out and the server is left with a process list filled with apache2 processes that need to be killed with killall. It does seem to be a concurrency problem but I can't figure out where it comes from. Any help would be great!

Evert

Evert Lammerts wrote:
Hi all,

On a php driven webpage we do 2 asynchronous requests with an xmlhttprequest immediately after the page loads. The first request returns without a problem, the second never returns and leaves the server (ubuntu dapper drake with apache 2.2.4) with an apache process using (according to the top command) 100% CPU. If you try, in the same browser window, to go to an other page the request wont load and stopping the server does not kill the process.

I did some debugging with xDebug on the second request after the pageload (which does not use any database functions) and doing this, or in other words delaying the response of the service, lets the request finish fine and doesn't leave the server with an unfinished process.

Any idea what to do?

I have the impression this has something to do with concurrent request handling, MPM. We're using prefork and the settings are:

# prefork MPM # StartServers: number of server processes to start # MinSpareServers: minimum number of server processes which are kept spare # MaxSpareServers: maximum number of server processes which are kept spare # MaxClients: maximum number of server processes allowed to start # MaxRequestsPerChild: maximum number of requests a server process serves <IfModule mpm_prefork_module> StartServers 10 MinSpareServers 10 MaxSpareServers 100 MaxClients 150 MaxRequestsPerChild 0
</IfModule>

Thanks, Evert





---------------------------------------------------------------------
The official User-To-User support forum of the Apache HTTP Server Project.
See <URL:http://httpd.apache.org/userslist.html> for more info.
To unsubscribe, e-mail: users-unsubscribe@xxxxxxxxxxxxxxxx
  "   from the digest: users-digest-unsubscribe@xxxxxxxxxxxxxxxx
For additional commands, e-mail: users-help@xxxxxxxxxxxxxxxx


[Index of Archives]     [Open SSH Users]     [Linux ACPI]     [Linux Kernel]     [Linux Laptop]     [Kernel Newbies]     [Security]     [Netfilter]     [Bugtraq]     [Squid]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Video 4 Linux]     [Device Mapper]

  Powered by Linux