Re: [PATCH 00/26] Zone write plugging

Bart Van Assche
2024-02-06T00:57:38Z

On 2/5/24 15:42, Damien Le Moal wrote:
> On 2/6/24 02:21, Bart Van Assche wrote:
>> On 2/1/24 23:30, Damien Le Moal wrote:
>>> The patch series introduces zone write plugging (ZWP) as the new
>>> mechanism to control the ordering of writes to zoned block devices.
>>> ZWP replaces zone write locking (ZWL) which is implemented only by
>>> mq-deadline today. ZWP also allows emulating zone append operations
>>> using regular writes for zoned devices that do not natively support this
>>> operation (e.g. SMR HDDs). This patch series removes the scsi disk
>>> driver and device mapper zone append emulation to use ZWP emulation.
>>
>> How are SCSI unit attention conditions handled?
>
> ???? How does that have anything to do with this series ?
> Whatever SCSI sd is doing with unit attention conditions remains the same. I did
> not touch that.

I wrote my question before I had realized that this patch series
restricts the number of outstanding writes to one per zone. Hence,
there is no risk of unaligned write pointer errors due to reordering
of writes due to unit attention conditions. Hence, my question can
be ignored :-)

Thanks,

Bart.