Re: [PATCH] MAINTAINERS: move the BFQ io scheduler to orphan state

[Jens Axboe <axboe@kernel.dk>]

On 9/5/24 12:05 PM, Linus Walleij wrote:
> On Thu, Sep 5, 2024 at 4:58?PM Jens Axboe <axboe@kernel.dk> wrote:
>> On 9/5/24 7:03 AM, Linus Walleij wrote:
> 
>>> Which production? For singlequeue devices it is pretty widespread.
>>
>> We tried it at one point internally at Meta, and it was not pretty.
> 
> I didn't know you used any singlequeue devices.
> 
> If you used it on multiqueue devices, well that can't be recommended.

Of course we have single queue devices, anything that isn't nvme is
basically single queue.

>>> Maybe we should propose these rules to the main udev repository
>>> so that they also go into Debian and we get even wider use?
>>
>> I know you like to push for it to be the default, and I always push back
>> because I don't think it's stable enough for that, and now we have the
>> added complication that it hasn't been maintained for quite a while.
>> So no, I don't think so.
> 
> The reason I like it personally is that it has actually saved me from
> crashing my machine by preserving interactivity on a (single queue)
> device:
> https://people.kernel.org/linusw/bfq-saved-me-from-thrashing

I'd consider that largely anecdotal at this point.

> For Androids and chromebooks it keeps the device interactive
> during heavy disk (eMMC) activity, such as when Android
> updates a pile of apps (.apk files).

I'm somewhat dubious that that problem could not be solved in a much
simpler way than what is BFQ.

-- 
Jens Axboe