Hi, Our tests showed that the write packing improved the performance of the write sequential operations: Long write operation: ---------------------- no-packing: 15.8 MB/s packed commands patch (both READ and WRITE packing are enabled): 23.3 MB/s Several parallel write operations (sum of all the write throughputs): --------------------------- no-packing: 17.1 MB/s packed commands patch(both READ and WRITE packing are enabled): 25 MB/s Parallel long read and long write operations (write throughput): ----------------------------------------------------------------- no-packing: 12.2 MB/s packed commands patch (both READ and WRITE packing are enabled): 16.3 MB/s Parallel short read and long write operations (write throughput): ----------------------------------------------------------------- no-packing: 15.4 MB/s packed commands patch (both READ and WRITE packing are enabled): 16.4 MB/s Several Parallel short read and short write operations (sum of all the write throughputs): -------------------------------------------------------------------------- no-packing: 12.5 MB/s packed commands patch (both READ and WRITE packing are enabled): 15.5 MB/s Random read and random write: ------------------------------ I checked the random read and random write IOPs by using the IOZONE application. There was a slight degradation in the read results due to the packing and no improvements in the write results. The results are: IOZONE file size of 100M: no-packing: random read: 4675, random write: 729 packed commands patch (both READ and WRITE packing are enabled): random read: 4557 random write: 723 IOZONE file size of 256M: no-packing: random read: 4632, random write: 744 packed commands patch (both READ and WRITE packing are enabled): random read: 4498, random write: 742 Thanks, Maya Erez Consultant for Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum > Hi. merez. > > Would you share random read speed with us ? > > And Write speed also.. > > Thanks. > > 2012/3/1 <merez@xxxxxxxxxxxxxx>: >>> This patch supports packed command of eMMC4.5 device. >>> Several reads(or writes) can be grouped in packed command >>> and all data of the individual commands can be sent in a >>> single transfer on the bus. >>> >>> Signed-off-by: Seungwon Jeon <tgih.jun@xxxxxxxxxxx> >>> --- >>>  drivers/mmc/card/block.c  |  496 >>> +++++++++++++++++++++++++++++++++++++++++-- >>>  drivers/mmc/card/queue.c  |  48 ++++- >>>  drivers/mmc/card/queue.h  |  13 ++ >>>  drivers/mmc/core/mmc_ops.c |   1 + >>>  include/linux/mmc/core.h  |   4 + >>>  5 files changed, 535 insertions(+), 27 deletions(-) >>> >> Hi, >> >> We ran performance tests on the packed commands patch. We found out that >> enabling the read packing didn't improve the performance in any of the >> scenarios we ran (see the detailed results below). >> Therefore, we suggest to move the read packing code to a different patch >> and approve only the write packing code for now. The read packing adds >> complexity to the code and we don't see a point in adding it while the >> intention is to disable it. >> >> Test results: >> >> Long read operation: >> ---------------------- >> no-packing: 39.5 MB/s >> packed commands patch (both READ and WRITE packing are enabled): 39.5 >> MB/s >> packed commands patch + enabling only READ packing: 39.5 MB/s >> >> Several parallel read operations (sum of all the read throughputs): >> --------------------------- >> no-packing: 42.6 MB/s >> packed commands patch(both READ and WRITE packing are enabled): 38 MB/s >> packed commands patch + enabling only READ packing: 38.2 MB/s >> >> Parallel long read and long write operations (read throughput): >> ----------------------------------------------------------------- >> no-packing: 23.8 MB/s >> packed commands patch (both READ and WRITE packing are enabled): 12.6 >> MB/s >> packed commands patch + enabling only READ packing: 12.5 MB/s >> >> Parallel short read and long write operations (read throughput): >> ----------------------------------------------------------------- >> no-packing: 22.9 MB/s >> packed commands patch (both READ and WRITE packing are enabled): 8.4 >> MB/s >> packed commands patch + enabling only READ packing: 8.6 MB/s >> >> Several Parallel short read and short write operations (sum of all the >> read throughputs): >> -------------------------------------------------------------------------- >> no-packing: 41.6 MB/s >> packed commands patch (both READ and WRITE packing are enabled): 35 MB/s >> packed commands patch + enabling only READ packing: 36 MB/s >> >> Thanks, >> Maya Erez >> Consultant for Qualcomm Innovation Center, Inc. >> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum >> >> >> >> >> >> -- >> 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 > -- 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
