Re: block/throttle and burst bucket

[Alberto Garcia]

On Thu 25 Feb 2021 06:34:48 PM CET, Peter Lieven <pl@kamp.de> wrote:
> I was wondering if there is a way to check from outside (qmp etc.) if
> a throttled block device has exceeded the iops_max_length seconds of
> time bursting up to iops_max and is now hard limited to the iops limit
> that is supplied?
>
> Would it be also a good idea to exetend the accounting to account for
> requests that must have waited before being sent out to the backend
> device?

No, there's no such interface as far as I'm aware. I think one problem
is that throttling is now done using a filter, that can be inserted
anywhere in the node graph, and accounting is done at the BlockBackend
level.

We don't even have a query-block-throttle function. I actually started
to write one six years ago but it was never finished.

Berto