Re: remove exofs, the T10 OSD code and block/scsi bidi support V3

Boaz Harrosh
2018-12-23T12:24:30Z

On 19/12/18 16:43, Christoph Hellwig wrote:
> On Mon, Nov 26, 2018 at 07:11:10PM +0200, Boaz Harrosh wrote:
>> On 11/11/18 15:32, Christoph Hellwig wrote:
>>> The only real user of the T10 OSD protocol, the pNFS object layout
>>> driver never went to the point of having shipping products, and we
>>> removed it 1.5 years ago. Exofs is just a simple example without
>>> real life users.
>>>
>>
>> You have failed to say what is your motivation for this patchset? What
>> is it you are trying to fix/improve.
>
> Drop basically unused support, which allows us to
>
> 1) reduce the size of every kernel with block layer support, and
> even more for every kernel with scsi support

Do you have numbers? its mainly code-segment so I don't think you will see
any real life measurable difference.

> 2) reduce the size of the critical struct request structure by
> 128 bits, thus reducing the memory used by every blk-mq driver
> significantly, never mind the cache effects

128 bits? I see the "struct request *next_rq;"
is there another one?

It could share space with elv; && flush;
Do you want a patch?

> 3) stop having the maintainance overhead for this code in the
> block layer, which has been rather painful at times
>

I hear you man. Life is pain. But is it really such an overhead?
I mean it is already implemented. What else is there to do?
Please please show me? (Sorry for being slow)

Jai Maa
Boaz