Re: [External Mail]Re: [PATCH v3] block: move non sync requests complete flow to softirq

[章辉 <zhanghui31@xiaomi.com>]

On 2024/9/4 12:29, Christoph Hellwig wrote:
> On Tue, Sep 03, 2024 at 11:49:28AM -0600, Jens Axboe wrote:
>> The elephant in the room here is why an 80M completion takes 100 msec?
>> That seems... insane.
>>
>> That aside, doing writes that big isn't great for latencies in general,
>> even if they are orders of magnitude smaller (as they should be). Maybe
>> this is solvable by just limiting the write size here.
>>
>> But it really seems out of line for a write that size to take 100 msec
>> to process.
> pagecache state processing is quite inefficient, we had to limit
> the number of them for XFS to avoid latency problems a while ago.
> Note that moving to folios means you can process a lot more data
> with the same number of completion iterations as well.  I'd suggest
> the submitter looks into that for whatever file system they are using.
>
hi Christoph,

The F2FS file system is used on the smartphone, and end_io uses page
traversal instead of folio traversal.
I will confirm the plan to migrate to folio. Thank you!

Thanks
Zhang