Re: [Qemu-devel] scsi-hd with discard_granularity and unmap results in Aborted Commands

[Paolo Bonzini <pbonzini@redhat.com>]

Il 18/11/2012 23:00, Stefan Priebe ha scritto:
> Hi Paolo,
> 
> Am 06.11.2012 23:42, schrieb Paolo Bonzini:
>>
>>> i wantes to use scsi unmap with rbd. rbd documention says you need to
>>> set discard_granularity=512 for the device. I'm using qemu 1.2.
>>>
>>> If i set this and send an UNMAP command i get this kernel output:
>>
>> The discard request is failing.  Please check why with a breakpoint on
>> rbd_aio_discard_wrapper or scsi_handle_rw_error for example.
>>
>> Paolo
> 
> I'm sorry the discard requests aren't failing. Qemu / Block driver
> starts to cancel a bunch of requests.

That is being done in the kernel (the guest, I think) because the UNMAPs
are taking too long.

Paolo

> [   39.577194] sd 2:0:0:1: [sdb]
> [   39.577194] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
> [   39.577194] sd 2:0:0:1: [sdb]
> [   39.577194] Sense Key : Aborted Command [current]
> [   39.577194] sd 2:0:0:1: [sdb]
> [   39.577194] Add. Sense: I/O process terminated
> [   39.577194] sd 2:0:0:1: [sdb] CDB:
> [   39.577194] Write same(16): 93 08 00 00 00 00 04 7f ff f7 00 62 00 09
> 00 00
> [   39.577194] end_request: I/O error, dev sdb, sector 75497463