Re: What does Timeout in the httpd.conf file accomplish?

[Jeroen Geilman <jeroen@xxxxxxxxx>]

On 06/20/2011 02:38 AM, Zaccone, Warren wrote:

Running  multiple copies of this script concurrently brings httpd into a hang state, that it will not recover from without manually restarting the httpd server.

 

ab -n 300 -c 300 http://myserver/mysite/loop.php

You're requesting a single URL 300 times concurrently.
This means that apache has to dedicate 300 threads at once to this purpose.

If you're not running worker, and your minspare is lower than 250 or so, it's going to take MINUTES to even get to number 300.

As documented, when many new (prefork) threads are being requested at once, apache will only  spawn one per second, to protect itself from attacks and runaway processes.

 

<?php

/*  loop.php */

 

while (1) sleep (20);

 

?>

And the request does nothing for 20 seconds before returning.

What exactly are you testing here ?

I have timeout set to 900 but it does not appear to be working.  What does timeout in the httpd.conf do?

As documented, Timeout determines the maximum number of seconds that a single request may take.

 

Will the httpd.conf  timeout protect the server from such scripts or  is there something else.

Yes, Timeout works on the HTTP level, so everything sent over HTTP is affected by it.

This means everything.

 

I am configured using Prefork

Then that apachebench run you show above is bloody stupid.

 

settings are:

 

Timeout 900

MaxKeepAliveRequests 100

StartServers        5

MinSpareServers     5

MaxSpareServers     10

MaxClients          256

You can't even SERVE 300 concurrent requests.

MaxRequestsPerChild   0

If you run PHP, this kills apache.
Eventually.

 

# pstack 22040 (root)

You have no idea what you are doing.

-- 
J.