Found the improved version of Peter Eisch's plugin attached to http://www.nntp.perl.org/group/perl.qpsmtpd/2006/03/msg4710.html. This includes caching of the system load and adds a cache_time config parameter.

This commit is contained in:
Richard Siddall 2014-03-21 09:40:01 -04:00
parent 95102e68c5
commit 04fc9327b7

55
plugins/loadcheck Normal file → Executable file
View File

@ -9,6 +9,12 @@ loadcheck
Only takes email transactions if the system load is at or below a Only takes email transactions if the system load is at or below a
specified level. specified level.
If this is running on a system that provides /kern/loadavg or
/proc/loadavg it will be used in stead of the 'uptime' command.
Once a load value is determined, it is cached for a period of time.
See the cache_time below.
=head1 CONFIG =head1 CONFIG
max_load max_load
@ -16,6 +22,11 @@ max_load
This is the 1 minute system load where we won't take transactions This is the 1 minute system load where we won't take transactions
if our load is higher than this value. (Default: 7) if our load is higher than this value. (Default: 7)
cache_time
A recently determined load value will be cached and used for the
assigned number of seconds. (Default: 10)
uptime uptime
The path to the command 'uptime' if different than the default. The path to the command 'uptime' if different than the default.
@ -23,6 +34,8 @@ uptime
Example: Example:
loadcheck cache_time 30
loadcheck max_load 7 uptime /usr/bin/uptime loadcheck max_load 7 uptime /usr/bin/uptime
=over 4 =over 4
@ -46,29 +59,59 @@ sub register {
$self->{_args}->{uptime} = '/usr/bin/uptime' $self->{_args}->{uptime} = '/usr/bin/uptime'
if (! defined $self->{_args}->{uptime}); if (! defined $self->{_args}->{uptime});
$self->{_args}->{cache_time} = 10
if (! defined $self->{_args}->{cache_time});
$self->{_load} = -1;
$self->{_time} = 0;
$self->register_hook("connect", "loadcheck"); $self->register_hook("connect", "loadcheck");
} }
sub loadcheck { sub loadcheck {
my ($self, $transaction) = @_; my ($self, $transaction) = @_;
my $hiload = 0; if (time() > ($self->{_time} + $self->{_args}->{cache_time})) {
# cached value expired
my $cmd = $self->{_args}->{uptime}; if ( -r '/kern/loadavg' ) { # *BSD
# contains fix-point scaling value
open(LD, "</kern/loadavg");
my $res = <LD>;
close LD;
my @vals = split(/ /, $res);
$self->{_load} = ($val[0] / $val[3]);
$self->{_time} = time();
$self->log(LOGDEBUG, "/kern/loadavg reported: $self->{_load}");
} elsif ( -r '/proc/loadavg' ) { # *inux
# contains decimal value
# contains fix-point scaling value
open(LD, "</proc/loadavg");
my $res = <LD>;
close LD;
$self->{_load} = (split(/ /, $res))[0];
$self->{_time} = time();
$self->log(LOGDEBUG, "/proc/loadavg reported: $self->{_load}");
} else {
# the various formats returned:
#10:33AM up 2:06, 1 user, load averages: 6.55, 3.76, 2.48 #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 # 12:29am 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 # 12:30am up 5 days, 12:43, 1 user, load average: 0.00, 0.00, 0.00
my $res = `$self->{_args}->{uptime}`; my $res = `$self->{_args}->{uptime}`;
if ($res =~ /aver\S+: (\d+\.\d+)/) { if ($res =~ /aver\S+: (\d+\.\d+)/) {
$hiload = $1; $self->{_load} = $1;
$self->{_time} = time();
$self->log(LOGDEBUG, "$self->{_args}->{uptime} reported: $self->{_load}");
}
}
} }
if ($hiload > $self->{_args}->{max_load}) { if ($self->{_load} > $self->{_args}->{max_load}) {
$self->log(LOGERROR, "local load too high: $hiload"); $self->log(LOGERROR, "local load too high: $self->{_load}");
return DENYSOFT; return DENYSOFT;
} }
return (DECLINED, "continuing with load: $hiload"); return (DECLINED, "continuing with load: $self->{_load}");
} }