original_kernel/fs/partitions
Nikanth Karthikesan 316d315bff block: Seperate read and write statistics of in_flight requests v2
Commit a9327cac44 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 0f78ab9899

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
..
Kconfig
Makefile
acorn.c
acorn.h
amiga.c
amiga.h
atari.c
atari.h
check.c block: Seperate read and write statistics of in_flight requests v2 2009-10-06 20:16:55 +02:00
check.h
efi.c
efi.h
ibm.c
ibm.h
karma.c
karma.h
ldm.c
ldm.h
mac.c
mac.h
msdos.c
msdos.h
osf.c
osf.h
sgi.c
sgi.h
sun.c
sun.h
sysv68.c
sysv68.h
ultrix.c
ultrix.h