Sys::Statistics::LinuxUser Contributed Perl DocumentaSys::Statistics::Linux(3)NAMESys::Statistics::Linux - Front-end module to collect system statistics
SYNOPSIS
use Sys::Statistics::Linux;
my $lxs = Sys::Statistics::Linux->new(
sysinfo => 1,
cpustats => 1,
procstats => 1,
memstats => 1,
pgswstats => 1,
netstats => 1,
sockstats => 1,
diskstats => 1,
diskusage => 1,
loadavg => 1,
filestats => 1,
processes => 1,
);
sleep 1;
my $stat = $lxs->get;
DESCRIPTIONSys::Statistics::Linux is a front-end module and gather different linux
system information like processor workload, memory usage, network and
disk statistics and a lot more. Refer the documentation of the
distribution modules to get more information about all possible
statistics.
MOTIVATION
My motivation is very simple... every linux administrator knows the
well-known tool sar of sysstat. It helps me a lot of time to search
for system bottlenecks and to solve problems, but it's hard to parse
the output if you want to store the statistics into a database. So I
thought to develope Sys::Statistics::Linux. It's not a replacement but
it should make it simpler to you to write your own system monitor.
If Sys::Statistics::Linux doesn't provide statistics that are strongly
needed then let me know it.
TECHNICAL NOTE
This distribution collects statistics by the virtual /proc filesystem
(procfs) and is developed on the default vanilla kernel. It is tested
on x86 hardware with the distributions RHEL, Fedora, Debian, Ubuntu,
Asianux, Slackware, Mandriva and openSuSE (SLES on zSeries as well but
a long time ago) on kernel versions 2.4 and/or 2.6. It's possible that
it doesn't run on all linux distributions if some procfs features are
deactivated or too much modified. As example the linux kernel 2.4 can
compiled with the option "CONFIG_BLK_STATS" what turn on or off block
statistics for devices.
Don't give up if some of the modules doesn't run on your hardware! Tell
me what's wrong and I will try to solve it! You just have to make the
first move and to send me a mail. :-)
VIRTUAL MACHINES
Note that if you try to install or run "Sys::Statistics::Linux" under
virtual machines on guest systems that some statistics are not
available, such as "SockStats", "PgSwStats" and "DiskStats". The reason
is that not all /proc data are passed to the guests.
If the installation fails then try to force the installation with
cpan> force install Sys::Statistics::Linux
and notice which tests fails, because this statistics maybe not
available on the virtual machine - sorry.
DELTAS
The statistics for "CpuStats", "ProcStats", "PgSwStats", "NetStats",
"DiskStats" and "Processes" are deltas, for this reason it's necessary
to initialize the statistics before the data can be prepared by
"get()". These statistics can be initialized with the methods "new()",
"set()" and "init()". For any option that is set to 1, the statistics
will be initialized by the call of "new()" or "set()". The call of
init() re-initialize all statistics that are set to 1 or 2. By the
call of "get()" the initial statistics will be updated automatically.
Please refer the section "METHODS" to get more information about the
usage of "new()", "set()", "init()" and "get()".
Another exigence is to sleep for a while - at least for one second -
before the call of "get()" if you want to get useful statistics. The
statistics for "SysInfo", "MemStats", "SockStats", "DiskUsage",
"LoadAVG" and "FileStats" are no deltas. If you need only one of these
information you don't need to sleep before the call of "get()".
The method "get()" prepares all requested statistics and returns the
statistics as a Sys::Statistics::Linux::Compilation object. The inital
statistics will be updated.
MANUAL PROC(5)
The Linux Programmer's Manual
http://www.kernel.org/doc/man-pages/online/pages/man5/proc.5.html
If you have questions or don't understand the sense of some statistics
then take a look into this awesome documentation.
OPTIONS
All options are identical with the package names of the distribution in
lowercase. To activate the gathering of statistics you have to set the
options by the call of "new()" or "set()". In addition you can
deactivate statistics with "set()".
The options must be set with one of the following values:
0 - deactivate statistics
1 - activate and init statistics
2 - activate statistics but don't init
In addition it's possible to pass a hash reference with options.
my $lxs = Sys::Statistics::Linux->new(
processes => {
init => 1,
pids => [ 1, 2, 3 ]
},
netstats => {
init => 1,
initfile => $file,
},
);
Option "initfile" is useful if you want to store initial statistics on
the filesystem.
my $lxs = Sys::Statistics::Linux->new(
cpustats => {
init => 1,
initfile => '/tmp/cpustats.yml',
},
diskstats => {
init => 1,
initfile => '/tmp/diskstats.yml',
},
netstats => {
init => 1,
initfile => '/tmp/netstats.yml',
},
pgswstats => {
init => 1,
initfile => '/tmp/pgswstats.yml',
},
procstats => {
init => 1,
initfile => '/tmp/procstats.yml',
},
);
Example:
#!/usr/bin/perl
use strict;
use warnings;
use Sys::Statistics::Linux;
my $lxs = Sys::Statistics::Linux->new(
pgswstats => {
init => 1,
initfile => '/tmp/pgswstats.yml'
}
);
$lxs->get(); # without to sleep
The initial statistics are stored to the temporary file:
#> cat /tmp/pgswstats.yml
---
pgfault: 397040955
pgmajfault: 4611
pgpgin: 21531693
pgpgout: 49511043
pswpin: 8
pswpout: 272
time: 1236783534.9328
Every time you call the script the initial statistics are loaded/stored
from/to the file. This could be helpful if you doesn't run it as
daemon and if you want to calculate the average load of your system
since the last call. Do you understand? I hope so :)
To get more information about the statistics refer the different
modules of the distribution.
sysinfo - Collect system information with Sys::Statistics::Linux::SysInfo.
cpustats - Collect cpu statistics with Sys::Statistics::Linux::CpuStats.
procstats - Collect process statistics with Sys::Statistics::Linux::ProcStats.
memstats - Collect memory statistics with Sys::Statistics::Linux::MemStats.
pgswstats - Collect paging and swapping statistics with Sys::Statistics::Linux::PgSwStats.
netstats - Collect net statistics with Sys::Statistics::Linux::NetStats.
sockstats - Collect socket statistics with Sys::Statistics::Linux::SockStats.
diskstats - Collect disk statistics with Sys::Statistics::Linux::DiskStats.
diskusage - Collect the disk usage with Sys::Statistics::Linux::DiskUsage.
loadavg - Collect the load average with Sys::Statistics::Linux::LoadAVG.
filestats - Collect inode statistics with Sys::Statistics::Linux::FileStats.
processes - Collect process statistics with Sys::Statistics::Linux::Processes.
METHODSnew()
Call "new()" to create a new Sys::Statistics::Linux object. You can
call "new()" with options. This options would be passed to the method
"set()".
Without options
my $lxs = Sys::Statistics::Linux->new();
Or with options
my $lxs = Sys::Statistics::Linux->new( cpustats => 1 );
Would do nothing
my $lxs = Sys::Statistics::Linux->new( cpustats => 0 );
It's possible to call "new()" with a hash reference of options.
my %options = (
cpustats => 1,
memstats => 1
);
my $lxs = Sys::Statistics::Linux->new(\%options);
set()
Call "set()" to activate or deactivate options.
The following example would call "new()" and initialize
"Sys::Statistics::Linux::CpuStats" and delete the object of
"Sys::Statistics::Linux::SysInfo".
$lxs->set(
processes => 0, # deactivate this statistic
pgswstats => 1, # activate the statistic and calls new() and init() if necessary
netstats => 2, # activate the statistic and call new() if necessary but not init()
);
It's possible to call "set()" with a hash reference of options.
my %options = (
cpustats => 2,
memstats => 2
);
$lxs->set(\%options);
get()
Call "get()" to get the collected statistics. "get()" returns a
Sys::Statistics::Linux::Compilation object.
my $lxs = Sys::Statistics::Linux->new(\%options);
sleep(1);
my $stat = $lxs->get();
Or you can pass the time to sleep with the call of "get()".
my $stat = $lxs->get($time_to_sleep);
Now the statistcs are available with
$stat->cpustats
# or
$stat->{cpustats}
Take a look to the documentation of Sys::Statistics::Linux::Compilation
for more information.
init()
The call of "init()" initiate all activated statistics that are
necessary for deltas. That could be helpful if your script runs in a
endless loop with a high sleep interval. Don't forget that if you call
"get()" that the statistics are deltas since the last time they were
initiated.
The following example would calculate average statistics for 30
minutes:
# initiate cpustats
my $lxs = Sys::Statistics::Linux->new( cpustats => 1 );
while ( 1 ) {
sleep(1800);
my $stat = $lxs->get;
}
If you just want a current snapshot of the system each 30 minutes and
not the average then the following example would be better for you:
# do not initiate cpustats
my $lxs = Sys::Statistics::Linux->new( cpustats => 2 );
while ( 1 ) {
$lxs->init; # init the statistics
my $stat = $lxs->get(1); # get the statistics
sleep(1800); # sleep until the next run
}
If you want to write a simple command line utility that prints the
current workload to the screen then you can use something like this:
my @order = qw(user system iowait idle nice irq softirq total);
printf "%-20s%8s%8s%8s%8s%8s%8s%8s%8s\n", 'time', @order;
my $lxs = Sys::Statistics::Linux->new( cpustats => 1 );
while ( 1 ){
my $cpu = $lxs->get(1)->cpustats;
my $time = $lxs->gettime;
printf "%-20s%8s%8s%8s%8s%8s%8s%8s%8s\n",
$time, @{$cpu->{cpu}}{@order};
}
settime()
Call "settime()" to define a POSIX formatted time stamp, generated with
localtime().
$lxs->settime('%Y/%m/%d %H:%M:%S');
To get more information about the formats take a look at "strftime()"
of POSIX.pm or the manpage strftime(3).
gettime()
"gettime()" returns a POSIX formatted time stamp, @foo in list and $bar
in scalar context. If the time format isn't set then the default
format "%Y-%m-%d %H:%M:%S" will be set automatically. You can also set
a time format with "gettime()".
my $date_time = $lxs->gettime;
Or
my ($date, $time) = $lxs->gettime();
Or
my ($date, $time) = $lxs->gettime('%Y/%m/%d %H:%M:%S');
EXAMPLES
A very simple perl script could looks like this:
use strict;
use warnings;
use Sys::Statistics::Linux;
my $lxs = Sys::Statistics::Linux->new( cpustats => 1 );
sleep(1);
my $stat = $lxs->get;
my $cpu = $stat->cpustats->{cpu};
print "Statistics for CpuStats (all)\n";
print " user $cpu->{user}\n";
print " nice $cpu->{nice}\n";
print " system $cpu->{system}\n";
print " idle $cpu->{idle}\n";
print " ioWait $cpu->{iowait}\n";
print " total $cpu->{total}\n";
Set and get a time stamp:
use strict;
use warnings;
use Sys::Statistics::Linux;
my $lxs = Sys::Statistics::Linux->new();
$lxs->settime('%Y/%m/%d %H:%M:%S');
print $lxs->gettime, "\n";
If you want to know how the data structure looks like you can use
"Data::Dumper" to check it:
use strict;
use warnings;
use Sys::Statistics::Linux;
use Data::Dumper;
my $lxs = Sys::Statistics::Linux->new( cpustats => 1 );
sleep(1);
my $stat = $lxs->get;
print Dumper($stat);
How to get the top 5 processes with the highest cpu workload:
use strict;
use warnings;
use Sys::Statistics::Linux;
my $lxs = Sys::Statistics::Linux->new( processes => 1 );
sleep(1);
my $stat = $lxs->get;
my @top5 = $stat->pstop( ttime => 5 );
BACKWARD COMPATIBILITY
The old options and keys - CpuStats, NetStats, etc - are still
available but deprecated! It's not possible to access the statistics
via Sys::Statistics::Linux::Compilation and it's not possible to call
"search()" and "psfind()" if you use the old options.
You should use the new options and access the statistics over the
accessors
$stats->cpustats
or directly with
$stats->{cpustats}
PREREQUISITES
Carp
POSIX
Test::More
Time::HiRes
UNIVERSAL
EXPORTS
No exports.
TODOS
* Are there any wishs from your side? Send me a mail!
REPORTING BUGS
Please report all bugs to <jschulz.cpan(at)bloonix.de>.
AUTHOR
Jonny Schulz <jschulz.cpan(at)bloonix.de>.
COPYRIGHT
Copyright (C) 2006-2008 by Jonny Schulz. All rights reserved.
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
perl v5.14.1 2011-06-20 Sys::Statistics::Linux(3)
