Hi Geert, On Wednesday 29 October 2014 10:59:48 Geert Uytterhoeven wrote: > On Wed, Oct 29, 2014 at 10:49 AM, Laurent Pinchart wrote: > > I've performed quick SDHI performance tests yesterday. Read performance > > were around 7.5% lower with DMA support. Write performances varied but > > seemed similar on average. > > > > - PIO > > > > # time dd if=/dev/mmcblk1 of=/mnt/ram/mmc.bin count=32768 bs=4096 > > 262144+0 records in > > 262144+0 records out > > 262144 records? Did it get split in 512 byte records? I knew I should have replaced the whole results instead of copying only the lines I thought had changed between tests :-) The times correspond to 32768 blocks of 4kB despite what the number of records say. > > # time dd of=/dev/mmcblk1 if=/mnt/ram/mmc.bin count=32768 bs=4096 > > 32+0 records in > > 32+0 records out > > Only 32 records? > > > - DMA > > > > # time dd if=/dev/mmcblk1 of=/mnt/ram/mmc.bin count=32768 bs=4096 > > 32+0 records in > > 32+0 records out > > Only 32 records? > > > # time dd of=/dev/mmcblk1 if=/mnt/ram/mmc.bin count=32768 bs=4096 > > 32768+0 records in > > 32768+0 records out > > OK -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
