Apache-LoadAvgLimit

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


License
Artistic-1.0-Perl

Contributors

Ryo Okamoto


See all contributors


Documentation

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 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 [email protected]

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 [email protected]

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.