Nikanth Karthikesan 316d315bff block: Seperate read and write statistics of in_flight requests v2
Commit a9327cac440be4d8333bba975cbbf76045096275 added seperate read
and write statistics of in_flight requests. And exported the number
of read and write requests in progress seperately through sysfs.

But  Corrado Zoccolo <czoccolo@gmail.com> reported getting strange
output from "iostat -kx 2". Global values for service time and
utilization were garbage. For interval values, utilization was always
100%, and service time is higher than normal.

So this was reverted by commit 0f78ab9899e9d6acb09d5465def618704255963b

The problem was in part_round_stats_single(), I missed the following:
        if (now == part->stamp)
                return;

-       if (part->in_flight) {
+       if (part_in_flight(part)) {
                __part_stat_add(cpu, part, time_in_queue,
                                part_in_flight(part) * (now - part->stamp));
                __part_stat_add(cpu, part, io_ticks, (now - part->stamp));

With this chunk included, the reported regression gets fixed.

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>

--
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-10-06 20:16:55 +02:00
..
2005-04-16 15:20:36 -07:00
2006-12-07 08:39:30 -08:00
2005-04-16 15:20:36 -07:00
2006-12-07 08:39:30 -08:00
2005-04-16 15:20:36 -07:00
2008-07-25 10:53:44 -07:00
2005-04-16 15:20:36 -07:00
2008-07-25 10:53:26 -07:00
2008-07-25 10:53:26 -07:00
2005-04-16 15:20:36 -07:00
2005-04-16 15:20:36 -07:00
2005-04-16 15:20:36 -07:00
2005-04-16 15:20:36 -07:00
2007-02-10 23:50:00 -08:00
2005-04-16 15:20:36 -07:00
2005-04-16 15:20:36 -07:00