Re: [PATCH RFC 04/29] fsverity: add per-sb workqueue for post read processing

From: Tejun Heo
Date: Tue Aug 12 2025 - 15:53:52 EST


Hello,

On Tue, Aug 12, 2025 at 09:43:50AM +0200, Christoph Hellwig wrote:
...
> Andrey (or others involved with previous versions): is interference
> with the log completion workqueue what you ran into?
>
> Tejun, are you going to prepare a patch to fix the rescuer priority?

NVM, I was confused. All rescuers, regardless of the associated workqueue,
set their nice level to MIN_NICE. IIRC, the rationale was that by the time
rescuer triggers the queued work items already have experienced noticeable
latencies and that rescuer invocations would be pretty rare. I'd be
surprised if rescuer behavior is showing up as easily observable
interferences in most cases. The system should already be thrashing quite a
bit for rescuers to be active and whatever noise rescuer behavior might
cause should usually be drowned by other things.

Thanks.

--
tejun