LP #952727: pt-diskstats shows incorrect wr_mb_s
Description
Environment
Smart Checklist
Activity
lpjirasync January 24, 2018 at 3:23 PM
**Comment from Launchpad by: Baron Schwartz on: 12-06-2012 17:26:16
The fix will be released in a couple of days.
lpjirasync January 24, 2018 at 3:23 PM
**Comment from Launchpad by: Baron Schwartz on: 13-04-2012 21:50:06
This bug was supposed to be fixed in 2.1.1 but the branch was never merged. Launchpad seems to have confused us.
lpjirasync January 24, 2018 at 3:23 PM
**Comment from Launchpad by: Baron Schwartz on: 16-03-2012 17:14:05
My last couple of comments were really directed at Brian. If you use --group-by=all with this tool, it will do what you expect. We can change this option's default value in the next release so it works as you expect.
So, Vadim, we don't need any more info. Your workaround for now is --group-by=all.
lpjirasync January 24, 2018 at 3:23 PM
**Comment from Launchpad by: Vadim Tkachenko on: 16-03-2012 16:58:52
Guys I am lost. What kind of input you need from me ?
I personally never had needs in an average value calculated from the first measurement.
I always use last - previous.
For me it would be helpful if I get that number by default. I used a filtering by disk only to show information relevant for a disk I am interested in.
lpjirasync January 24, 2018 at 3:23 PM
**Comment from Launchpad by: Baron Schwartz on: 16-03-2012 15:48:09
Actually I believe --group-by=all does produce the expected behavior with no further ado. It also produces something reasonable when given a sample file.
Details
Assignee
UnassignedUnassignedReporter
lpjirasynclpjirasync(Deactivated)Priority
High
Details
Details
Assignee
Reporter
lpjirasyncPriority
HighSmart Checklist
Open Smart Checklist
Smart Checklist
Open Smart Checklist
Smart Checklist
**Reported in Launchpad by Vadim Tkachenko last update 19-06-2012 20:02:23
iostat -dxm 5 shows:
Device: rrqm/s wrqm/s r/s w/s rMB/s wMB/s avgrq-sz avgqu-sz await svctm %util
sda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
sdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
scd0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
fioa 0.00 0.00 0.00 7765.00 0.00 121.32 32.00 0.00 4.02 0.00 0.00
fiob 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Device: rrqm/s wrqm/s r/s w/s rMB/s wMB/s avgrq-sz avgqu-sz await svctm %util
sda 0.00 0.20 0.00 0.60 0.00 0.00 10.67 0.00 0.00 0.00 0.00
sdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
scd0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
fioa 0.00 0.00 0.00 7540.40 0.00 117.82 32.00 0.00 4.00 0.00 0.00
fiob 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Device: rrqm/s wrqm/s r/s w/s rMB/s wMB/s avgrq-sz avgqu-sz await svctm %util
sda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
sdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
scd0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
fioa 0.00 0.00 0.00 7500.20 0.00 117.18 32.00 0.00 3.98 0.00 0.00
fiob 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Device: rrqm/s wrqm/s r/s w/s rMB/s wMB/s avgrq-sz avgqu-sz await svctm %util
sda 0.00 0.20 0.00 0.60 0.00 0.00 10.67 0.00 0.00 0.00 0.00
sdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
scd0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
fioa 0.00 0.00 0.00 7452.80 0.00 116.44 32.00 20.08 4.03 0.02 15.94
fiob 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Device: rrqm/s wrqm/s r/s w/s rMB/s wMB/s avgrq-sz avgqu-sz await svctm %util
sda 6.20 0.00 0.80 0.20 0.03 0.00 57.60 0.03 31.80 22.00 2.20
sdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
scd0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
fioa 0.00 0.00 0.00 7450.40 0.00 116.41 32.00 20.22 4.02 0.02 15.92
fiob 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
pt-diskstat shows
#ts device rd_s rd_avkb rd_mb_s rd_mrg rd_cnc rd_rt wr_s wr_avkb wr_mb_s wr_mrg wr_cnc wr_rt busy in_prg io_s qtime stime
{160} fioa 0.1 4.0 0.0 0% 0.0 26.6 30924.6 6.0 181.5 0% 777.5 25.1 47% 0 30924.6 23.3 0.0
{161} fioa 0.1 4.0 0.0 0% 0.0 26.6 30778.5 6.0 181.1 0% 772.9 25.1 47% 0 30778.6 23.2 0.0
{162} fioa 0.1 4.0 0.0 0% 0.0 26.6 30634.3 6.0 180.7 0% 768.3 25.1 46% 0 30634.4 23.2 0.0
{163} fioa 0.1 4.0 0.0 0% 0.0 26.6 30492.0 6.1 180.3 0% 763.7 25.0 46% 0 30492.1 23.1 0.0
{164} fioa 0.1 4.0 0.0 0% 0.0 26.6 30352.7 6.1 179.9 0% 759.2 25.0 46% 0 30352.8 23.1 0.0
while sysbench is:
[ 280s] reads: 0.00 MB/s writes: 120.01 MB/s fsyncs: 0.00/s response time: 0.045ms (95%)
[ 290s] reads: 0.00 MB/s writes: 116.24 MB/s fsyncs: 0.00/s response time: 0.045ms (95%)
[ 300s] reads: 0.00 MB/s writes: 121.96 MB/s fsyncs: 0.00/s response time: 0.045ms (95%)
[ 310s] reads: 0.00 MB/s writes: 118.33 MB/s fsyncs: 0.00/s response time: 0.045ms (95%)
[ 320s] reads: 0.00 MB/s writes: 114.20 MB/s fsyncs: 0.00/s response time: 0.045ms (95%)
[ 330s] reads: 0.00 MB/s writes: 118.77 MB/s fsyncs: 0.00/s response time: 0.045ms (95%)
[ 340s] reads: 0.00 MB/s writes: 119.28 MB/s fsyncs: 0.00/s response time: 0.045ms (95%)
so device is doing close to 120 MB/s,
while
pt-diskstats shows 180
I am using async io mode in sysbench