On 10/30/2014 06:46 AM, Brian Foster wrote: > On Wed, Oct 29, 2014 at 04:38:22PM -0500, Stan Hoeppner wrote: >> On 10/29/2014 01:47 PM, Eric Sandeen wrote: >>> On 10/29/14 1:37 PM, Brian Foster wrote: >>>> On Tue, Oct 28, 2014 at 12:35:29PM -0500, Eric Sandeen wrote: >>>>> Today, this geometry: >>>>> >>>>> # modprobe scsi_debug opt_blks=2048 dev_size_mb=2048 >>>>> # blockdev --getpbsz --getss --getiomin --getioopt /dev/sdd >>>>> 512 >>>>> 512 >>>>> 512 >>>>> 1048576 >>>>> >>>>> will result in a warning at mkfs time, like this: >>>>> >>>>> # mkfs.xfs -f -d su=64k,sw=12 -l su=64k /dev/sdd >>>>> mkfs.xfs: Specified data stripe width 1536 is not the same as the volume stripe width 2048 >>>>> >>>>> because our geometry discovery thinks it looks like a >>>>> valid striping setup which the commandline is overriding. >>>>> However, a stripe unit of 512 really isn't indicative of >>>>> a proper stripe geometry. >>>>> >>>> >>>> So the assumption is that the storage reports a non-physical block size >>>> for minimum and optimal I/O sizes for geometry detection. There was a >>>> real world scenario of this, right? Any idea of the configuration >>>> details (e.g., raid layout) that resulted in an increased optimal I/O >>>> size but not minimum I/O size? >>> >>> Stan? :) >> >> Yeah, it was pretty much what you pasted sans the log su, and it was a >> device-mapper device: >> >> # mkfs.xfs -d su=64k,sw=12 /dev/dm-0 >> > > What kind of device is dm-0? I use linear devices regularly and I don't > see any special optimal I/O size reported: It's a dm-multipath device. I pasted details up thread. Here, again: # multipath -ll 3600c0ff0003630917954075401000000 dm-0 Tek,DH6554 size=44T features='0' hwhandler='0' wp=rw |-+- policy='round-robin 0' prio=50 status=active | `- 9:0:0:3 sdj 8:144 active ready running `-+- policy='round-robin 0' prio=10 status=enabled `- 1:0:0:3 sdf 8:80 active ready running # blockdev --getpbsz --getss --getiomin --getioopt /dev/dm-0 512 512 512 1048576 # blockdev --getpbsz --getss --getiomin --getioopt /dev/sdj 512 512 512 1048576 # blockdev --getpbsz --getss --getiomin --getioopt /dev/sdf 512 512 512 1048576 Cheers, Stan _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
