COMPAREANDWRITE needs to be ported to bs_aio too, but porting it and WRITESAME too to bs_aio should be straightforward. I can do a patch for that perhaps over the next few days. Possibly. Unfortunately, I never use bs_aio myself, I only use bs_rdwr, and it seems that TGTD and bs_aio is completely broken. I tried to compile and install it under both ubuntu and fedora right now but it just dumps core as soon as you start sending any kind of I/O to it. As I am not familiar with bs_aio I cant tell how long it will take to fix it, or perhaps someone else can help look at it too. But as for now, bs_aio is pretty borked :-( As soon as bs_aio is fixed I can port WRITESAME and COMPAREANDWRITE to it. On Sun, Aug 18, 2013 at 6:16 PM, Moussa Ba (moussaba) <moussaba@xxxxxxxxxx> wrote: > I will collect the wireshark and send the data. But based on the available documentation on VAAI, it implements 0x89 (ATS or Compare and Write), 0x83 (XCOPY), 0x93 (WRITE_SAME). > > How is COMPAREANDWRITE enabled? > Is it a stable feature? > Is it supported by aio? > > Moussa > > -----Original Message----- > From: ronnie sahlberg [mailto:ronniesahlberg@xxxxxxxxx] > Sent: Sunday, August 18, 2013 5:20 PM > To: Moussa Ba (moussaba) > Cc: stgt@xxxxxxxxxxxxxxx > Subject: Re: WRITE_SAME aio support > > On Sun, Aug 18, 2013 at 5:08 PM, Moussa Ba (moussaba) > <moussaba@xxxxxxxxxx> wrote: >> Our device is a high performance PCIe drive. aio is better. > > I see. > The TGTD LUN, is it a normal LUN or have you activated thin-provisioning for it? > > Can you compile tgtd from scratch and test? > If that is feasible, you can change usr/sbc.c and remove > WRITESAME10/16 completely from tgtd. > Towards the end of that file there is a definition of what commands > the emulated disk devices support : > > static struct device_type_template sbc_template = { > ... > > Indices 0x41 and 0x93 refer to the two WRITESAME versions. > If you change these two lines : > {sbc_rw,}, /* WRITE_SAME10 */ > ... > {sbc_rw,}, /* WRITE_SAME_16 */ > > to instead be > {spc_illegal_op,}, > > Then WRITESAME10/16 will be disabled and you shouldnt get those > warnings in the logs. > > > I can try adding WRITESAME10/16 support to tgtd sometime in the next few days. > Would it be possible for you to test those patches for me ? > > > > > > >> Any plans for tgt to support ATS, full copy and other VAAI primitives? > > Sure. > Do you have a list of which SCSI commands these refer to? > I assume COMPAREANDWRITE and XCOPY at least. > > We have COMPAREANDWRITE in TGTD but it is not enabled by default. > Could you collect a wireshark trace and send to me so I can see what > the commands VMWARE sends looks like? If so I can give it a try to > implement something. > > > >> >> Moussa >> >> >> >> -------- Original message -------- >> From: ronnie sahlberg <ronniesahlberg@xxxxxxxxx> >> Date: 08/18/2013 17:04 (GMT-08:00) >> To: "Moussa Ba (moussaba)" <moussaba@xxxxxxxxxx> >> Cc: stgt@xxxxxxxxxxxxxxx >> Subject: Re: WRITE_SAME aio support >> >> >> 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 -- 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
