#!/usr/bin/perl

use Getopt::Long;
use strict;
use warnings;

my $vm_name = "";
my $interval = 10;

GetOptions ("vm_name=s" => \$vm_name, "interval=i" => \$interval) or die 'Syntax error';

die 'Syntax error' unless $vm_name;

my $me = $$;
`ps axu | grep jvm-stats.pl | grep $vm_name | grep -v axu | grep -v $me | awk '{print \$2}' | xargs kill -TERM 2>&1 > /dev/null`;
`ps axu | grep jps | grep $vm_name | grep -v axu | awk '{print \$2}' | xargs kill -TERM 2>&1 > /dev/null`;

my $pid = 0;
$SIG{TERM} = sub {
  if ($pid) {
    `kill -TERM $pid`;
  }
  exit 0;
};

sub trim {
  my $s = shift;
  $s =~ s/^\s+|\s+$//g;
  return $s;
};

my $host = trim(`hostname`);
my $name = lc($vm_name);

while(1) {
  my $process = trim(`jps | grep $vm_name | awk '{print \$1}'` || '');
  if (length($process) > 0) {
    `ps axu | grep jstat | grep $process | grep -v axu | awk '{print \$2}' | xargs kill -TERM 2>&1 > /dev/null`;
    $pid = open(OUT, "jstat -gc $process ${interval}s |");
    my $first_line = <OUT>;
    while (my $line = <OUT>) {
      my $time = trim(`date +%s`);
      # S0C S1C S0U S1U EC EU OC OU PC PU YGC YGCT FGC FGCT GCT
      my ($s0c, $s1c, $s0u, $s1u, $ec, $eu, $oc, $ou, $pc, $pu, $ygc, $ygct, $fgc, $fgct, $gct) = map { trim($_) } split(/\s+/, trim($line));
      $fgc = int($fgc);
      $fgct = int($fgct);
      $ygc = int($ygc);
      $ygct = int($ygct);
      $fgct = $fgct * 1000;
      $ygct = $ygct * 1000;
      $pc = $pc * 1000;
      $pu = $pu * 1000;
      $oc = $oc * 1000;
      $ou = $ou * 1000;
      $ec = $ec * 1000;
      $eu = $eu * 1000;
      $s0c = $s0c * 1000;
      $s0u = $s0u * 1000;
      $s1c = $s1c * 1000;
      $s1u = $s1u * 1000;
      print "PUTVAL $host/jvm/counter-$name.gc $time:$fgc\n";
      print "PUTVAL $host/jvm/counter-$name.gc_time $time:$fgct\n";
      print "PUTVAL $host/jvm/counter-$name.ygc $time:$ygc\n";
      print "PUTVAL $host/jvm/counter-$name.ygc_time $time:$ygct\n";
      print "PUTVAL $host/jvm/gauge-$name.perm_capacity interval=$interval N:$pc\n";
      print "PUTVAL $host/jvm/gauge-$name.perm_size interval=$interval N:$pu\n";
      print "PUTVAL $host/jvm/gauge-$name.old_capacity interval=$interval N:$oc\n";
      print "PUTVAL $host/jvm/gauge-$name.old_size interval=$interval N:$ou\n";
      print "PUTVAL $host/jvm/gauge-$name.eden_capacity interval=$interval N:$ec\n";
      print "PUTVAL $host/jvm/gauge-$name.eden_size interval=$interval N:$eu\n";
      print "PUTVAL $host/jvm/gauge-$name.survivor0_capacity interval=$interval N:$s0c\n";
      print "PUTVAL $host/jvm/gauge-$name.survivor0_size interval=$interval N:$s0u\n";
      print "PUTVAL $host/jvm/gauge-$name.survivor1_capacity interval=$interval N:$s1c\n";
      print "PUTVAL $host/jvm/gauge-$name.survivor1_size interval=$interval N:$s1u\n";
    }
  }
  sleep($interval);
}