From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: Bug using ramp_time shows cpu over 100% References: <3ccceea7625d474b8afd2a6f6a7ab0ef@BOWEX36-B.micron.com> From: Jens Axboe Message-ID: <566796DC.2040308@kernel.dk> Date: Tue, 8 Dec 2015 19:50:04 -0700 MIME-Version: 1.0 In-Reply-To: <3ccceea7625d474b8afd2a6f6a7ab0ef@BOWEX36-B.micron.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit To: "Deyoung Hong (dhong)" , "fio@vger.kernel.org" List-ID: On 12/08/2015 02:45 PM, Deyoung Hong (dhong) wrote: > I saw the response on http://www.spinics.net/lists/fio/msg04392.html (didn't get the email), so I'm pasting it here. > > I git pulled the latest fio code and observed the specified changes. I compiled and ran the latest code but still seeing the same problem: > > =============== > test: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, ioengine=libaio, iodepth=1 > fio-2.2.12-50-g5261 > Starting 1 thread > > test: (groupid=0, jobs=1): err= 0: pid=10726: Tue Dec 8 13:40:21 2015 > read : io=799740KB, bw=79966KB/s, iops=19991, runt= 10001msec > slat (usec): min=0, max=11, avg= 0.10, stdev= 0.30 > clat (usec): min=26, max=2624, avg=49.03, stdev=34.07 > lat (usec): min=35, max=2624, avg=49.12, stdev=34.07 > clat percentiles (usec): > | 1.00th=[ 36], 5.00th=[ 36], 10.00th=[ 36], 20.00th=[ 37], > | 30.00th=[ 37], 40.00th=[ 38], 50.00th=[ 38], 60.00th=[ 39], > | 70.00th=[ 40], 80.00th=[ 70], 90.00th=[ 79], 95.00th=[ 87], > | 99.00th=[ 92], 99.50th=[ 94], 99.90th=[ 225], 99.95th=[ 298], > | 99.99th=[ 2128] > bw (KB /s): min= 0, max=81072, per=95.01%, avg=75974.80, stdev=17896.56 > lat (usec) : 50=71.32%, 100=28.42%, 250=0.19%, 500=0.04%, 750=0.01% > lat (usec) : 1000=0.01% > lat (msec) : 2=0.01%, 4=0.01% > cpu : usr=99.99%, sys=0.00%, ctx=8, majf=0, minf=0 > IO depths : 1=157.5%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, >=64=0.0% > submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0% > complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0% > issued : total=r=199935/w=0/d=0, short=r=0/w=0/d=0, drop=r=0/w=0/d=0 > latency : target=0, window=0, percentile=100.00%, depth=1 > > Run status group 0 (all jobs): > READ: io=799740KB, aggrb=79966KB/s, minb=79966KB/s, maxb=79966KB/s, mint=10001msec, maxt=10001msec This is showing 99.99% usr time, for a polled driver that doesn't seem crazy. Why do you think it's broken? -- Jens Axboe