If it is VMWARE then it probably uses WRITESAME10/16 for unmap/discard purposes. For now, can you try using bs_rdwr instead of bs_aio ? Longer term I will do a patch for * add WRITESAME10/16 + unmap support to bs_aio * make "indicate unmap support based on whether the backend supports it or not" On Sun, Aug 18, 2013 at 4:57 PM, Moussa Ba (moussaba) <moussaba@xxxxxxxxxx> wrote: > The LUN as seen by VMWare shows WRITE_SAME support. Not sure what is uses for discard > > > -------- Original message -------- > From: ronnie sahlberg <ronniesahlberg@xxxxxxxxx> > Date: 08/18/2013 16:55 (GMT-08:00) > To: "Moussa Ba (moussaba)" <moussaba@xxxxxxxxxx> > Cc: stgt@xxxxxxxxxxxxxxx > Subject: Re: WRITE_SAME aio support > > > Your initiator uses WS10/16 for unmap/discard ? > (i.e. you mount the filesystem using -o discard in the guest) > > STGT currently offers "I support unmapping using both WS10 and 16". We > probably should only do this > for backends that supports these operations, == bs_rdwr.c and not > indicate support for the others. > > > What we probably need to do here is to make the support for > WRITESAME10/16 with unmap support optional > on whether the backend supports it. > I can look at adding this once I get some other changes in. > > > > On Wed, Aug 14, 2013 at 2:41 PM, Moussa Ba (moussaba) > <moussaba@xxxxxxxxxx> wrote: >> I am seeing a LOT of WRITE_SAME error messages in the tgt logs. I understand it is not implemented for aio, my question is will this affect array performance . We are using tgt to host datastores for a virtualization workload. >> >> >> tgtd: bs_aio_cmd_submit(211) WRITE_SAME not yet supported for AIO backend >> >> >> Moussa >> -- >> To unsubscribe from this list: send the line "unsubscribe stgt" 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 stgt" 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 stgt" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
