Re: new plugin: check_system_load

[Peter Eisch]

On 3/7/08 3:39 PM, "Steve Kemp" <[EMAIL PROTECTED]> wrote:

> 
> This seems like rather an obvious idea:  Reject new
> connections if the system load is too high.  But surprisingly
> there seem to be no plugins which I could find implementing it.
> 

I had posted this one to the list back a couple years ago.  It works on
linux, bsd'en and solaris.  Maybe on hpux too.

peter



#!/usr/bin/perl

=head1 NAME

loadcheck

=head1 DESCRIPTION

Only takes email transactions if the system load is at or below a
specified level.  

=head1 CONFIG

max_load

  This is the 1 minute system load where we won't take transactions
if our load is higher than this value.  (Default: 7)

uptime

  The path to the command 'uptime' if different than the default.
(Default: /usr/bin/uptime)

Example:

loadcheck max_load 7 uptime /usr/bin/uptime

=over 4

=head1 AUTHOR

Written by Peter Eisch <[EMAIL PROTECTED]>.

=cut

my $VERSION = 0.01;

sub register {
  my ($self, $qp, @args) = @_;

  %{$self->{_args}} = @args;

  $self->{_args}->{max_load} = 7
      if (! defined $self->{_args}->{max_load});

  $self->{_args}->{uptime} = '/usr/bin/uptime'
      if (! defined $self->{_args}->{uptime});
  
  $self->register_hook("connect", "loadcheck");
}

sub loadcheck {
  my ($self, $transaction) = @_;

  my $hiload = 0;

  my $cmd = $self->{_args}->{uptime};
  #10:33AM  up  2:06, 1 user, load averages: 6.55, 3.76, 2.48
  # 12:29am  2 users,  load average: 0.05, 0.05, 0.06
  # 12:30am  up 5 days, 12:43,  1 user,  load average: 0.00, 0.00, 0.00

  my $res = `$self->{_args}->{uptime}`;
  if ($res =~ /aver\S+: (\d+\.\d+)/) {
      $hiload = $1;
  }

  if ($hiload > $self->{_args}->{max_load}) {
      $self->log(LOGERROR, "local load too high: $hiload");
      return DENYSOFT;
  }

  return (DECLINED, "continuing with load: $hiload");
}