Hi Chris, Do you see any issues with this patch? Regards, Subhash > -----Original Message----- > From: Subhash Jadavani [mailto:subhashj@xxxxxxxxxxxxxx] > Sent: Wednesday, April 18, 2012 1:07 PM > To: 'Namjae Jeon' > Cc: 'Chris Ball'; 'linux-mmc@xxxxxxxxxxxxxxx'; 'linux-arm- > msm@xxxxxxxxxxxxxxx' > Subject: RE: [PATCH v1 1/1] mmc: block: replace __blk_end_request() with > blk_end_request() > > Hi Namjae, > > > -----Original Message----- > > From: Namjae Jeon [mailto:linkinjeon@xxxxxxxxx] > > Sent: Wednesday, April 18, 2012 11:12 AM > > To: Subhash Jadavani > > Cc: Chris Ball; linux-mmc@xxxxxxxxxxxxxxx; > > linux-arm-msm@xxxxxxxxxxxxxxx > > Subject: Re: [PATCH v1 1/1] mmc: block: replace __blk_end_request() > > with > > blk_end_request() > > > > Hi. Subhash. > > > > Would you share which option you used in LMDD, iozone test ? > > Following are the commands. Page cache is flushed before next iteration. > Original numbers shared were average of almost 10 iterations. > > LMDD: > 100MB file read/write: > write: > lmdd if=internal of=/data/datafile bs=128k count=800 > flush=1 sync=1 > read: > lmdd if=/data/datafile of=internal bs=128k flush=1 > sync=1 > > IOZONE: > 100MB file read/write: > Write: > iozone -i0 -s100m -r128k -e -w -f /data/datafile -U > /data/ > Read: > iozone -i1 -s100m -r128k -e -f /data/datafile -U /data/ > > Regards, > Subhash > > > > > Thanks. > > > > 2012/4/18 Subhash Jadavani <subhashj@xxxxxxxxxxxxxx>: > > > Hi Chris, > > > > > >> -----Original Message----- > > >> From: linux-arm-msm-owner@xxxxxxxxxxxxxxx [mailto:linux-arm-msm- > > >> owner@xxxxxxxxxxxxxxx] On Behalf Of Subhash Jadavani > > >> Sent: Wednesday, April 11, 2012 12:22 AM > > >> To: 'Chris Ball' > > >> Cc: linux-mmc@xxxxxxxxxxxxxxx; linux-arm-msm@xxxxxxxxxxxxxxx > > >> Subject: RE: [PATCH v1 1/1] mmc: block: replace __blk_end_request() > > >> with > > >> blk_end_request() > > >> > > >> > > >> > > >> > -----Original Message----- > > >> > From: Chris Ball [mailto:cjb@xxxxxxxxxx] > > >> > Sent: Wednesday, April 11, 2012 12:08 AM > > >> > To: Subhash Jadavani > > >> > Cc: linux-mmc@xxxxxxxxxxxxxxx; linux-arm-msm@xxxxxxxxxxxxxxx > > >> > Subject: Re: [PATCH v1 1/1] mmc: block: replace > > >> > __blk_end_request() with > > >> > blk_end_request() > > >> > > > >> > Hi, > > >> > > > >> > On Tue, Apr 10 2012, Subhash Jadavani wrote: > > >> > > This patch replaces all __blk_end_request() calls with > > >> > > blk_end_request() and __blk_end_request_all() calls with > > >> > > blk_end_request_all(). > > >> > > > > >> > > Testing done: 20 process concurrent read/write on sd card and > eMMC. > > >> > > Ran this test for almost a day on multicore system and no > > >> > > errors observed. > > >> > > > >> > Is there a measurable improvement in throughput or latency that > > >> > you can > > >> show > > >> > data for? > > >> > > >> This change was not meant for improving MMC throughput; it's > > >> basically > > > about > > >> becoming fair to other threads/interrupts in the system. By holding > > >> spin > > > lock > > >> and interrupts disabled for longer duration, we won't allow other > > >> threads/interrupts to run at all. > > >> Actually slight performance degradation at file system level can be > > > expected as > > >> we are not holding the spin lock during blk_update_bidi_request() > > >> which > > > means > > >> our mmcqd thread may get preempted for other high priority thread > > >> or any interrupt in the system. > > >> > > >> > > >> These are performance numbers (100MB file write) with eMMC running > > >> in DDR > > >> mode: > > >> > > >> Without this patch: > > >> Name of the Test Value Unit > > >> LMDD Read Test 53.79 MBPS > > >> LMDD Write Test 18.86 MBPS > > >> IOZONE Read Test 51.65 MBPS > > >> IOZONE Write Test 24.36 MBPS > > >> > > >> With this patch: > > >> > > >> Name of the Test Value Unit > > >> LMDD Read Test 52.94 MBPS > > >> LMDD Write Test 16.70 MBPS > > >> IOZONE Read Test 52.08 MBPS > > >> IOZONE Write Test 23.29 MBPS > > >> > > >> Read numbers are fine. Write numbers are bit down (especially LMDD > > >> write), may be because write requests normally have large transfer > > >> size and which means there are chances that while mmcq is executing > > >> blk_update_bidi_request(), it may get interrupted by interrupts or > > >> other > > > high > > >> priority thread. > > > > > > Any thoughts/suggestions on this patch and numbers? > > > > > > Regards, > > > Subhash > > >> > > >> Regards, > > >> Subhash > > >> > > >> > > > >> > Thanks, > > >> > > > >> > - Chris. > > >> > -- > > >> > Chris Ball <cjb@xxxxxxxxxx> <http://printf.net/> One Laptop > > >> > Per Child > > >> > > >> -- > > >> To unsubscribe from this list: send the line "unsubscribe linux-arm- > msm" > > > in the > > >> body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo > info > > >> at http://vger.kernel.org/majordomo-info.html > > > > > > -- > > > 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 -- 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
