Hi, Maya Erez <merez@xxxxxxxxxxxxxx> wrote: > > 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. > Thank you for test. What is your test tool? Is there any improvement point we can discuss for packed read? Thanks, Seungwon Jeon. > 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
