Hi Jens, Thanks for the command. I was looking for something like this. However, I am still confused on the time stamp calculation. My Binary file had the starting time as "26.040173218 seconds" , but with the below command, cat file_54657438_1000lines.bin | blkparse - | less 8,0 60 0 0.000000000 54657438 Q R 24014152 + 8 [(null)] 8,0 60 0 66.860158593 54657438 Q R 805379152 +8 [(null)] 8,0 60 0 80.644832628 54657438 Q R 24014160 + 8 [(null)] The first line starts at 0 timestamp and then 66sec etc. I dont understand how the 66sec is calculated in the above blkparse command. Shouldnt it be 26.040173218 sec ? I do see 26.040173218 in the binary file and checked this using a binary viewer.Attached is the binary viewer of the file. Please help me understand. Thanks, Lakshmi On Thu, Apr 10, 2014 at 5:07 PM, Jens Axboe <axboe@xxxxxxxxx> wrote: > On 04/10/2014 12:25 PM, Lakshmi wrote: >> >> Hi Jens, >> >> I am seeing a strange problem. I have a 47KB Blkparsed binary file >> and I tried replaying it with and without the "replay_no_stall" >> option. >> >> With the "replay_no_stall" option, I am seeing some IOPS >> happening.Please see below. >> WITH "REPLAY_NO_STALL=1" >> ===================================================== >> job9: (g=0): rw=read, bs=4K-4K/4K-4K/4K-4K, ioengine=sync, iodepth=1 >> fio-2.1.7 >> Starting 1 process >> Jobs: 1 (f=2): [M] [-.-% done] [1064KB/72KB/0KB /s] [266/18/0 iops] >> [eta 00m:00s] >> job9: (groupid=0, jobs=1): err= 0: pid=34226: Thu Apr 10 12:00:54 2014 >> read : io=3792.0KB, bw=1126.3KB/s, iops=281, runt= 3367msec >> clat (usec): min=88, max=8536, avg=3546.19, stdev=1469.46 >> lat (usec): min=88, max=8536, avg=3546.35, stdev=1469.47 >> ===================================================== >> However, when I don't set the "REPLAY_NO_STALL" option, I see 0 >> IOPS.Please see below >> job9: (g=0): rw=read, bs=4K-4K/4K-4K/4K-4K, ioengine=sync, iodepth=1 >> fio-2.1.7 >> Starting 1 process >> >> job9: (groupid=0, jobs=1): err= 0: pid=33979: Thu Apr 10 10:39:42 2014 >> read : io=3792.0KB, bw=2004B/s, iops=0, runt=1937594msec >> clat (usec): min=87, max=14320, avg=4763.37, stdev=2001.45 >> lat (usec): min=87, max=14320, avg=4763.52, stdev=2001.50 >> =========================================================== >> >> My starting time in the blkparsed binary file is 26.040173218 seconds >> and last time is 26.150699031. >> >> Attached is the binary file I am using to replay. >> >> I understand replay_no_stall option doesnt respect the timestamps, but >> without this option the job should be executing with the delays, and >> not sure why no OPS are reported. >> >> Any idea what is causing this strange behavior?Please help. > > > It reports no IOPS, because it's slow enough to not register any. The first > trace in the file is at timestamp 0.00 relative, and the last one is at > 31110.250640101. Check for yourself with: > > cat file_54657438_1000lines.bin | blkparse - | less > > -- > Jens Axboe >
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