Re: [PATCH 1/2] nvme: remove namespaces in parallel

[Qiliang Yuan <odys.yuan@gmail.com>]

On Mon, 2 Nov 2026 08:26:57 +0100, Hannes Reinecke wrote:
> On 11/2/26 7:14 AM, Qiliang Yuan wrote:
>> nvme_remove_namespaces() removes the namespaces of a controller one
>> after another. Each removal waits for RCU grace periods in
>> del_gendisk() for the namespace and for its multipath head, about
>> 20 ms in all.
>>
> But that isn't changed by calling async_schedule_domain, isn't it?

Right, each removal still waits about 20 ms. What changes is that the
waits overlap. A grace period is system-wide, so removals that wait at
the same time are released by the same grace periods instead of each
needing its own. Disconnect time over tcp, from the table in the
patch:

  namespaces  before              after
           8   170 /  171 ms       85 /  91 ms
          32   628 /  628 ms      294 / 293 ms
          64  1201 / 1308 ms      533 / 550 ms

> Other than that it looks fine.

Thanks for the review.

Qiliang