NAME

Apache::LoadAvgLimit - limiting client request by system CPU load-averages (deprecated)

SYNOPSIS

  in httpd.conf, simply

  <Location /perl>
    PerlInitHandler Apache::LoadAvgLimit
    PerlSetVar LoadAvgLimit 2.5
  </Location>

  or fully

  <Location /perl>
    PerlInitHandler Apache::LoadAvgLimit
    PerlSetVar LoadAvgLimit_1 3.00
    PerlSetVar LoadAvgLimit_5 2.00
    PerlSetVar LoadAvgLimit_15 1.50
    PerlSetVar LoadAvgRetryAfter 120
  </Location>

CAUTION

THIS MODULE IS MARKED AS DEPRECATED.

The module may still work for you, but consider switch to psgi like below:

  use Plack::Builder;
  use HTTP::Exception;
  use Sys::Load;

  builder {
      enable 'HTTPExceptions';
      enable_if { (Sys::Load::getload())[0] > 3.00 }
          sub { sub { HTTP::Exception::503->throw } };

      $app;
  };

You can run mod_perl1 application as psgi with Plack::Handler::Apache1.

DESCRIPTION

If system load-average is over the value of LoadAvgLimit*, Apache::LoadAvgLimit will try to reduce the machine load by returning HTTP status 503 (Service Temporarily Unavailable) to client browser.

Especially, it may be useful in <Location> directory that has heavy CGI, Apache::Registry script or contents-handler program.

PARAMETERS

LoadAvgLimit

When at least one of three load-averages (1, 5, 15 min) is over this value, returning status code 503.

LoadAvgLimit_1, LoadAvgLimit_5, LoadAvgLimit_15

When Each minute's load-averages(1, 5, 15 min) is over this value, returning status code 503.

LoadAvgRetryAfter

The second(s) that indicates how long the service is expected to be unavailable to browser. When this value exists, Retry-After field is automatically set.

AUTHOR

Ryo Okamoto <ryo@aquahill.net>

SEE ALSO

mod_perl(3), Apache(3), getloadavg(3), uptime(1), RFC1945, RFC2616, mod_loadavg

REPOSITORY

https://github.com/ryochin/p5-apache-loadavglimit

AUTHOR

Ryo Okamoto <ryo@aquahill.net>

COPYRIGHT & LICENSE

Copyright (c) Ryo Okamoto, all rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.