Re: [PATCH -next v3 00/25] md: synchronize io with array reconfiguration

From: Song Liu
Date: Fri Oct 06 2023 - 22:41:22 EST


On Fri, Oct 6, 2023 at 7:32 PM Yu Kuai <yukuai1@xxxxxxxxxxxxxxx> wrote:
>
> Hi,
>
> 在 2023/10/05 11:55, Song Liu 写道:
> > On Wed, Oct 4, 2023 at 8:42 PM Yu Kuai <yukuai1@xxxxxxxxxxxxxxx> wrote:
> >>
> >> Hi,
> >>
> >> 在 2023/09/29 3:15, Song Liu 写道:
> >>> Hi Kuai,
> >>>
> >>> Thanks for the patchset!
> >>>
> >>> A few high level questions/suggestions:
> >>
> >> Thanks a lot for these!
> >>>
> >>> 1. This is a big change that needs a lot of explanation. While you managed to
> >>> keep each patch relatively small (great job btw), it is not very clear why we
> >>> need these changes. Specifically, we are adding a new mutex, it is worth
> >>> mentioning why we cannot achieve the same goal without it. Please add
> >>> more information in the cover letter. We will put part of the cover letter in
> >>> the merge commit.
> >>
> >> Yeah, I realize that I explain too little. I will add background and
> >> design.
> >>>
> Can you take a look about this new cover letter?

I don't have time right now to look into all the details, but it looks
great at first glance. We can still edit it a little bit when applying the
patchset, but that may not be necessary.

Thanks,
Song

>
> ##### Backgroud
>
> Our testers started to test raid10 last year, and we found that there
> are lots of problem in the following test scenario:
>
> - add or remove disks to the array
> - issue io to the array