mpm_prefork and RAM

Re: mpm_prefork and RAM

by Nathan Wallach -
Number of replies: 0

The library browser is a memory hog as it renders many problems in a single Apache worker. Gateway quizes also have similar issues.

You can reduce the memory it will use somewhat by:

  • lowering MaxSpareServers    (don't waste too much space on idle workers)
  • lowering MaxRequestWorkers    (do not allow to many to run, to avoid swapping and performance degredation)
  • lowering MaxConnectionsPerChild   (meant to kill workers before they get very large)

Adding in /etc/apache2/conf-enabled/webwork.conf (or wherever the real webwork.conf is on your system)

  # size limiter for Apache2 use Apache2::SizeLimit;
  $Apache2::SizeLimit::MAX_PROCESS_SIZE = 340000;
  $Apache2::SizeLimit::MAX_UNSHARED_SIZE = 340000;
  $Apache2::SizeLimit::CHECK_EVERY_N_REQUESTS = 5;

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