#!/usr/bin/perl -w

use strict;
use Sun::Solaris::Kstat;
use POSIX qw(uname strftime);
use POSIX qw(sysconf _SC_PAGESIZE);

#
# Script from Solaris Internals Book http://www.solarisinternals.com
# (c) Richard McDougall and James Mauro
#

my ($interval, $count) = @ARGV;
my ($kstats, $now, $then, $mb);
$interval = 5 if (! defined($interval) || $interval < 1);
$count = -1 if (! $count);

# Get the system's page size and check that it is a power of two.
my $pagesize = sysconf(_SC_PAGESIZE);
unless (defined $pagesize and $pagesize =~ /^\d+$/ and $pagesize > 0) {
  die "$0: internal error: sysconf(_SC_PAGESIZE) did not return an ",
      "integer > 0.\n";
}
$mb = (1024 * 1024) / $pagesize;

$SIG{INT} = $SIG{QUIT} = $SIG{HUP} = sub { $count = 0; };

my $ks = Sun::Solaris::Kstat->new();

# Save initial stats values
print("prtmem started on ", strftime("%d/%m/%Y %T", localtime()),
      " on ", (uname())[1], ", sample interval $interval seconds\n\n");

print "                   Total      Kernel       Delta        Free
Delta\n";

# Loop the required number of times
while ($count == -1 || $count-- > 0)
{
   my $ts = strftime("%T", localtime());

   # Get and copy the new stats values
   $ks->update();
   $kstats = $ks->{unix};
   %{$now} = %{$kstats->{0}{system_pages}};

   # Skip unless we have both sets of stats
   if ($then) {
        my $delta = $now->{snaptime} - $then->{snaptime};
	printf("$ts    %12d%12d%12d%12d%12d\n", 
		$now->{physmem} / $mb,
		$now->{pp_kernel} / $mb, ($now->{pp_kernel} - $then->{pp_kernel}) /
$mb,
		$now->{pagesfree} / $mb, ($now->{pagesfree} - $then->{pagesfree}) /
$mb
		);
   }

   # Save the new stats
   $then = $now;
   $now = {};

   # Wait for a bit, then update the stats
   sleep($interval);
}