Re: [PATCH 7/7] iotests/281: Let NBD connection yield in iothread

[Vladimir Sementsov-Ogievskiy]

03.02.2022 19:30, Hanna Reitz wrote:
> Put an NBD block device into an I/O thread, and then read data from it,
> hoping that the NBD connection will yield during that read.  When it
> does, the coroutine must be reentered in the block device's I/O thread,
> which will only happen if the NBD block driver attaches the connection's
> QIOChannel to the new AioContext.  It did not do that after 4ddb5d2fde
> ("block/nbd: drop connection_co") and prior to "block/nbd: Move s->ioc
> on AioContext change", which would cause an assertion failure.
>
> To improve our chances of yielding, the NBD server is throttled to
> reading 64 kB/s, and the NBD client reads 128 kB, so it should yield at
> some point.
>
> Signed-off-by: Hanna Reitz<hreitz@redhat.com>


Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

--
Best regards,
Vladimir