#!/usr/bin/perl -w

=head1 NAME

iostat - Plugin for watching io-bound traffic (in KiloBytes) on disks

=head1 CONFIGURATION

No configuration

=head1 NOTES

=head2 DESCRIPTION

This version of iostat will report back the amount of I/O on a per
disk basis.  It includes the vpaths in it's report.  The I/O for a
vpath is the sum of the reads/writes of all the hdisks associated
with it.  It uses /usr/bin/iostat.

=head2 RESTRICTIONS

Not restricted to a particular user.

You will have to enable disk accounting for this to work correctly.
You can do this through 'smitty chgsys -> Continuously maintain DISK
I/O history', change this to true, or you can do it at the command
line with this command "chdev -l sys0 -a iostat='true'".

Note: If you have virtual paths, typical when gigabit fiber cards are
installed and attached to an ESS (Shark) or some sort of large disk
array, this will combine the I/O for all hdisks associated with a
vpath so you get global statistics for a vpath.  This is to avoid
having a list of hdisks that spans multiple pages.

=head1 AUTHOR

Unknown author

=head1 LICENSE

GPLv2

=head1 MAGIC MARKERS

 #%# family=auto
 #%# capabilities=autoconf

=cut

use strict;
use POSIX;

my($arg) = shift;

if($arg && $arg eq "autoconf") {
    if ( (-e "/usr/bin/iostat" && -X "/usr/bin/iostat") &&
	 (-e '/usr/sbin/lspv' && -X '/usr/sbin/lspv') ) {
        print "yes\n";
        exit 0;
    } else {
        print "no (Need /usr/bin/iostat and /usr/sbin/lspv)\n";
        exit 0;
    }
}

if($arg && $arg eq "config")
  {
    print "graph_title IOstat\n";
    print "graph_args --base 1024 --logarithmic\n";
    print "graph_vlabel KB / \${graph_period}\n";
    print "graph_category disk\n";
    my(@info) = getDiskIO("disk only");
    my($line);
    foreach $line (@info)
      {
        print "$line.label $line\n";
        print "$line.type COUNTER\n";
        print "$line.max 100000\n";
      }
    exit 0;
  }

my(@info) = getDiskIO('');
my($line);
foreach $line (@info)
  {print "$line";}
@info = processVPaths();
foreach $line (@info)
  {print "$line";}


sub getDiskIO
{
  my($diskOnly) = @_;
  my($line,@lineArray,@diskArray,$writes,$reads,$diskLine);
  if($diskOnly && $diskOnly eq 'disk only')
    {
      open DISKLIST, "/usr/sbin/lspv|egrep 'hdisk|vpath'|grep -v none|";
      while($line = <DISKLIST>)
        {
          @lineArray = split(/ +/,$line);
          push(@diskArray,"$lineArray[0]_read","$lineArray[0]_write");
        }
    }
  else
    {
      open DISKLIST, "/usr/sbin/lspv|grep hdisk|grep -v none|";
      while($line = <DISKLIST>)
        {
          @lineArray = split(/ +/,$line);
          $diskLine = `/usr/bin/iostat|grep $lineArray[0]`;
          @lineArray = split(/ +/,$diskLine);
          $writes = $lineArray[5];
          chomp($writes);
          $reads = $lineArray[4];
          chomp($reads);

          push(@diskArray,"$lineArray[0]_read.value $reads\n","$lineArray[0]_write.value $writes\n");
        }
    }
  return @diskArray
}

sub processVPaths
{
  open DISKLIST, "/usr/sbin/lspv|grep vpath|";
  my($line,$hdiskLine,@diskArray,$reads,$writes);
  while($line = <DISKLIST>)
    {
      my(@vpathArr) = split(/ +/,$line);
      my($vpathNum) = substr($vpathArr[0],index($vpathArr[0],"h")+1);
      open VPATHINFO, "/usr/bin/datapath query device $vpathNum|grep hdisk|";
      $reads = 0;
      $writes = 0;
      while($hdiskLine = <VPATHINFO>)
        {
          my(@hdiskInfo) = split(/ +/,$hdiskLine);
          my($hdisk) = substr($hdiskInfo[2],index($hdiskInfo[2],"/")+1);
          my($diskLine) = `/usr/bin/iostat|grep $hdisk`;
          my(@lineArray) = split(/ +/,$diskLine);
          $reads += $lineArray[4];
          $writes += $lineArray[5];
        }
      push(@diskArray,$vpathArr[0]."_read.value $reads\n",$vpathArr[0]."_write.value $writes\n");
    }
  return @diskArray;
}

sub printArray
{
  my($array,$spacer,$useNums,@labels) = @_;
  my($item,);
  my($count) = 0;

  foreach $item (@{$array})
    {
      if($useNums == 1)
        {print $count.substr($spacer,0,length($spacer)-length($count)).$item."\n";}
      else
        {print $labels[$count].substr($spacer,0,length($spacer)-length($labels[$count])).$item."\n";}
      $count++;
    }
}