Re: Vmware ESXi5 Build 623860 - UNMAP Bit

[Martin Svec <martin.svec@xxxxxxxx>]

Hi Stefan,

If you run commit e163b66985fa162bd7c1e29a049b336bc2790a2e then you 
already have the patch included and ESXi5 should work. But the patch 
does not entirely suppress WRITE_SAME errors. Before fallback to 
non-accelerated zeroing, ESXi tries WRITE_SAME at least once and 
probably re-tries it from time to time. I see these occasional 
WRITE_SAME errors too, but definitely not for every zeroing SCSI cmd. 
The same holds for "MODE SENSE: unimplemented page/subpage: 0x1c/0x02" 
error. If I remember this page has something to do with thin 
provisioning, SCSI guys should know better.

It would be fine to get an approval from VMware engineers that this 
behavior is really correct ;-)

Anyway, I see no performance or data integrity impact of these dmesg 
errors in my vSphere 5 lab setup.

Martin

Dne 3.4.2012 1:29, Nicholas A. Bellinger napsal(a):
> On Tue, 2012-03-27 at 14:26 +0200, Stefan Gourguis wrote:
> > Dear List,
> >
> > i have connected an new ESXi5 (Update1 Build) to an Debian 6 LIO Target (Git commit e163b66985fa162bd7c1e29a049b336bc2790a2e).
> > The Esxi Server is single FC connected to Lio (P2P)..
> > Lio-Target serves n 100 GB LVM Disk via iblock to the ESXi.
> > I started installing  an Windows 7 VM on this Datastore (VMFS 5.54)
> >
> > "Strong as a LIO-N" gives me a lot of Errors in  dmesg:
> >
> > [ 1146.241497] MODE SENSE: unimplemented page/subpage: 0x1c/0x02
> > [ 1231.742035] WRITE_SAME w/o UNMAP bit not supported for Block Discard Emulation
> > [ 1231.753493] WRITE_SAME w/o UNMAP bit not supported for Block Discard Emulation
> > [ 1231.765680] WRITE_SAME w/o UNMAP bit not supported for Block Discard Emulation
> > [ 1300.303536] WRITE_SAME w/o UNMAP bit not supported for Block Discard Emulation
> > [ 1300.308241] WRITE_SAME w/o UNMAP bit not supported for Block Discard Emulation
> > [ 1300.312904] WRITE_SAME w/o UNMAP bit not supported for Block Discard Emulation
> > [ 1313.008761] WRITE_SAME w/o UNMAP bit not supported for Block Discard Emulation
> > [ 1313.013449] WRITE_SAME w/o UNMAP bit not supported for Block Discard Emulation
> > [ 1313.018111] WRITE_SAME w/o UNMAP bit not supported for Block Discard Emulation
> > [ 1316.343687] WRITE_SAME w/o UNMAP bit not supported for Block Discard Emulation
> > [ 1316.348386] WRITE_SAME w/o UNMAP bit not supported for Block Discard Emulation
> > [ 1316.353041] WRITE_SAME w/o UNMAP bit not supported for Block Discard Emulation
> > [ 1320.468975] WRITE_SAME w/o UNMAP bit not supported for Block Discard Emulation
> > [ 1320.473646] WRITE_SAME w/o UNMAP bit not supported for Block Discard Emulation
> > [ 1320.478306] WRITE_SAME w/o UNMAP bit not supported for Block Discard Emulation
> > ...
> Hi Stefan,
>
> The bugfix to make this work by default w/o the extra esxcli call to
> explicitly disable VAAI on all LUNs was reported by Martin Svec, and
> went into v3.2-rc5 here:
>
> target: Fix unsupported WRITE_SAME sense payload
> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=67236c44741e250199ccd77f1115568e68cf8848
>
> However it appears I missed the CC to stable on this one..
>
> Greg-KH (CC'ed) would you mind including this into v3.1 and v3.0 stable
> releases for distros to pick up..?
>
> Thanks,
>
> --nab
>
>
>
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe target-devel" 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 target-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html