Re: [PATCH -next v2 0/7] limit the number of plugged bio

[Song Liu]

On Fri, May 12, 2023 at 2:43 AM Yu Kuai <yukuai1@xxxxxxxxxxxxxxx> wrote:
>
> Hi,
>
> 在 2023/04/26 16:20, Yu Kuai 写道:
> > From: Yu Kuai <yukuai3@xxxxxxxxxx>
> >
> > Changes in v2:
> >   - remove the patch to rename raid1-10.c
> >
> > This patchset tries to limit the number of plugged bio for raid1 and
> > raid10, which is done in the last patch, other patches are some refactor
> > and optimizations.
> >
> > This patchset is tested with a new test [1], this test triggers dirty
> > pages writeback for 10s, and in the meantime checks disk inflight.
> >
> > Before this patchset, test will fail because inflight exceed threshold
> > (threshold is set to 4096 in the test, in theory this can be mutch
> >   greater as long as there are enough dirty pages and memory).
> >
> > After this patchset, inflight is within 96 (MAX_PLUG_BIO * copies).
> >
> > [1] https://lore.kernel.org/linux-raid/20230426073447.1294916-1-yukuai1@xxxxxxxxxxxxxxx/
>
> Friendly ping...

I am sorry for the delay.

The set looks good overall, but I will need some more time to take a closer
look. A few comments/questions:

1. For functions in raid1-10.c, let's prefix them with raid1_ instead of md_*.
2. Do we need unplug_wq to be per-bitmap? Would a shared queue work?

Thanks,
Song