Since you are willing to test, can you test this patch? This patch adds support for WRITESAME10/16 to the bs_aio backend. It passes my tests for WRITESAME : ./bin/iscsi-test-cu iscsi://127.0.0.1/iqn.ronnie.test/1 --test SCSI.WriteSame*.* -V --dataloss (well one test fails but it fails for bs_rdwr too) Dont build against TGTD HEAD, it is broken for aio. Build against 1.0.38 On Sun, Aug 18, 2013 at 8:13 PM, Moussa Ba (moussaba) <moussaba@xxxxxxxxxx> wrote: > I just switched over to rdwr, might be safer anyway...So, how do I enable COMPAREANDWRITE on rdwr? > > Moussa > > -----Original Message----- > From: stgt-owner@xxxxxxxxxxxxxxx [mailto:stgt-owner@xxxxxxxxxxxxxxx] On Behalf Of ronnie sahlberg > Sent: Sunday, August 18, 2013 8:12 PM > To: Moussa Ba (moussaba) > Cc: stgt@xxxxxxxxxxxxxxx > Subject: Re: WRITE_SAME aio support > > 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
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