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I'm running CentOS 64 bit, and jsut found out I am running prefork MPM on my dual quad xeon. I was told worker will give me lower memory usage, and higher performance, since I run a very high traffic website.

If this is true, how do I do it?

Thank you

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3 Answers 3

up vote 12 down vote accepted

Edit: /etc/sysconfig/httpd



Restart, voila!

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Hi @RafiqManiar, by restart do you mean Apache or the whole server here? –  fuzzybee Feb 25 '13 at 5:04
Restart apache. sudo service httpd restart –  Rafiq Maniar Feb 25 '13 at 8:31

Edited: /etc/sysconfig/httpd

And uncommented:


After restarting httpd (service httpd restart) I get the following error:

Stopping httpd:                                            [  OK  ]
Starting httpd: httpd.worker: Syntax error on line 222 of /etc/httpd/conf/httpd.conf: Syntax error on line 9 of /etc/httpd/conf.d/php.conf: Cannot load /etc/httpd/modules/libphp5-zts.so into server: /etc/httpd/modules/libphp5-zts.so: cannot open shared object file: No such file or directory

You might need to install php-zts though.

yum install php-zts

After that no more error messages and httpd is starting normally with module worker active.

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It might be true, the only real way to find out is to test.

This is a compile time option so that would require a recompile of apache. Download the srpm, install it, modify the source, create a patch file, apply the patch file in the .spec file, rebuild the RPM, install the RPM. (That's a very quick description for a somewhat longer process.) Here is a more complete example.

Or you could just download the source, compile it, and install it. Which might be a better choice for testing purposes. I'd go the extra mile and create the RPM. You always want to create a re-producible environment, especially in a very high traffic situation.

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Worker MPM is available in CentOS and Debian/Ubuntu without recompiling. –  Rafiq Maniar Jan 11 '11 at 9:50

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