On 17/08/17 10:45, Bough Chen wrote: > >> -----Original Message----- >> From: linux-mmc-owner@xxxxxxxxxxxxxxx [mailto:linux-mmc- >> owner@xxxxxxxxxxxxxxx] On Behalf Of Adrian Hunter >> Sent: Thursday, August 10, 2017 8:08 PM >> To: Ulf Hansson <ulf.hansson@xxxxxxxxxx> >> Cc: linux-mmc <linux-mmc@xxxxxxxxxxxxxxx>; Bough Chen >> <haibo.chen@xxxxxxx>; Alex Lemberg <alex.lemberg@xxxxxxxxxxx>; >> Mateusz Nowak <mateusz.nowak@xxxxxxxxx>; Yuliy Izrailov >> <Yuliy.Izrailov@xxxxxxxxxxx>; Jaehoon Chung <jh80.chung@xxxxxxxxxxx>; >> Dong Aisheng <dongas86@xxxxxxxxx>; Das Asutosh >> <asutoshd@xxxxxxxxxxxxxx>; Zhangfei Gao <zhangfei.gao@xxxxxxxxx>; >> Sahitya Tummala <stummala@xxxxxxxxxxxxxx>; Harjani Ritesh >> <riteshh@xxxxxxxxxxxxxx>; Venu Byravarasu <vbyravarasu@xxxxxxxxxx>; >> Linus Walleij <linus.walleij@xxxxxxxxxx>; Shawn Lin <shawn.lin@xxxxxxxxxxxxxx> >> Subject: [PATCH V5 00/13] mmc: Add Command Queue support >> >> Hi >> >> Here is V5 of the hardware command queue patches without the software >> command queue patches. >> >> HW CMDQ offers 25% - 50% better random multi-threaded I/O. I see a slight 2% >> drop in sequential read speed but no change to sequential write. >> >> > Hi Adrian, > > I test the performance on the i.MX8. Here in my side, I use 'dd' to test the > sequential read/write speed, see a slight 3% drop for both read and write. > > --------------------------------------------- > | | read (KB/s)| write (KB/s) | > --------------------------------------------- > |CMDQ in HS400ES| 257 | 94.5 | > --------------------------------------------- > | HS400ES | 265 | 96.6 | > --------------------------------------------- > > For random multi-threaded I/O, I use 'fio' to test, the test command: > fio -filename=/mnt/test -direct=1 -iodepth 1 -thread -rw=randread - ioengine=psync -bs=4k -size=2G -numjobs=10 -runtime=60 -group_reporting - name=mytest > > I test 5 times, and get the average value. > For CMDQ in HS400ES > ---------------------------------------------------- > | block size | 4KB | 8KB | 16KB | > ---------------------------------------------------- > | random read | 26340KB/s | 51844KB/s | 85738KB/s | > ---------------------------------------------------- > | random write | 12691KB/s | 15879KB/s | 17535KB/s | > ---------------------------------------------------- > > HS400ES without CMDQ > ---------------------------------------------------- > | block size | 4KB | 8KB | 16KB | > ---------------------------------------------------- > | random read | 18585KB/s | 35041KB/s | 63880KB/s | > ---------------------------------------------------- > | random write | 16465KB/s | 19210KB/s | 22672KB/s | > ---------------------------------------------------- > > For random write from the test, I find every test value differ greatly no matter enable CMDQ or not. > >>From the test, I see CMDQ random read speed increase 34%~48%, but for random write, the speed > drop 17.4% ~ 33%. > > When you send software cmdq V5 patch, you give some explanation for the random write. But the > average random write speed also drops a lot, I think it is now a good news, which need attention! I tried your test and got quite variable results but did not see a drop: CQ 4K 8K 16K Random Write 10,374 KB/s 9,669 KB/s 10,712 KB/s Non-CQ 4K 8K 16K Random Write 9,898 KB/s 8,747 KB/s 9,098 KB/s But given the variability of results I would not conclude CQ was faster. I would suggest you run more tests and see if the trend continues. -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
