diff -r 000000000000 -r 624a9ab34425 disk_io_stat.pl
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/disk_io_stat.pl	Wed May 07 16:25:00 2014 +0200
@@ -0,0 +1,40 @@
+#!/usr/bin/perl
+# disk stat thru sys/block/<dev>stats
+
+$fbase = "/sys/block/";
+$devpattern = qr#^$base(dm-\d+|sd.+)$#i;
+
+$sleep = 1;
+
+%nodiff = ( 8 => 1 );
+
+@header = qw ( dev r-io r-merge r-sect r-tick w-io w-merge w-sect w-tick inflight iotick timeinQ );
+
+@devs = grep { s/^\s+|\s+$//g,1 } grep { /$devpattern/ } qx( ls $fbase );
+
+while( 1 ) {
+  print chr(27), "[2J", chr(27), '[f';
+  foreach $h (@header) {
+    printf "%-12s ", $h;
+  }
+  print "\n";
+
+  for $i ( 0 .. $#devs ) {
+    $s = qx( cat $fbase$devs[$i]/stat ); chomp $s; $s =~ s/^\s+|\s+$//g;
+    @a = split /\s+/, $s;
+  
+    print $devs[$i], "\t";
+    for $j ( 0 ..  $#a ) {
+      if( $nodiff{$j} ) {
+        printf "%12i;", $a[$j];
+      
+      } else {
+        printf "%12i ", $a[$j] - $prev[$i][$j];
+        $prev[$i][$j] = $a[$j];
+      }
+    }
+    print "\n";
+  }
+
+  sleep $sleep;
+}