On Mon, 3 Jun 2013, H. Peter Anvin wrote: > On 06/03/2013 11:35 AM, Martin K. Petersen wrote: > >>>>>> "hpa" == H Peter Anvin <hpa@xxxxxxxxx> writes: > > > > hpa> OK, so the device here says don't do this again, but fails the > > hpa> request anyway expecting the block device to pick up the slack. > > > > Yes, the block layer function will resort to writing out zeroes directly > > in this case. > > > > MD should not consider a rejected WRITE SAME a failure. > > > > We should probably add Joe Lawrence to this thread. > > Joe: basically it seems that the error behavior of md (at least raid10, > but probably raid1 as well) on WRITE SAME is wrong, and it causes the > RAID to abort. Martin is probably the expert here (I had extended his initial WRITE SAME support in MD raid0 to raid1 and raid10), but I can try failing a WS cmd using our San Blaze emulator to see the fall out. Just curious, what type drives were in your RAID and what does /sys/class/scsi_disk/*/max_write_same_blocks report? If you have a spare drive to test, maybe you could try a quick sg_write_same command to see how the drive reacts? -- Joe -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
