Hi Namjae,
> -----Original Message-----
> From: Namjae Jeon [mailto:[email protected]]
> Sent: Wednesday, April 18, 2012 11:12 AM
> To: Subhash Jadavani
> Cc: Chris Ball; [email protected]; [email protected]
> 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 <[email protected]>:
> > Hi Chris,
> >
> >> -----Original Message-----
> >> From: [email protected] [mailto:linux-arm-msm-
> >> [email protected]] On Behalf Of Subhash Jadavani
> >> Sent: Wednesday, April 11, 2012 12:22 AM
> >> To: 'Chris Ball'
> >> Cc: [email protected]; [email protected]
> >> Subject: RE: [PATCH v1 1/1] mmc: block: replace __blk_end_request()
> >> with
> >> blk_end_request()
> >>
> >>
> >>
> >> > -----Original Message-----
> >> > From: Chris Ball [mailto:[email protected]]
> >> > Sent: Wednesday, April 11, 2012 12:08 AM
> >> > To: Subhash Jadavani
> >> > Cc: [email protected]; [email protected]
> >> > 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 <[email protected]> <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 [email protected] 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 [email protected] More majordomo
> > info at http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
