Messages in this thread | | | Date | Wed, 18 Jun 2008 17:16:56 +0200 | From | "Carl Henrik Lunde" <> | Subject | Re: [PATCH 1/3] i/o bandwidth controller documentation |
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On Sat, Jun 7, 2008 at 00:27, Andrea Righi <righi.andrea@gmail.com> wrote: [...] > +3. Advantages of providing this feature > + > +* Allow QoS for block device I/O among different cgroups
I'm not sure if this can be called QoS, as it does not guarantee anything but throttling?
> +* The bandwidth limitations are guaranteed both for synchronous and > + asynchronous operations, even the I/O passing through the page cache or > + buffers and not only direct I/O (see below for details)
The throttling does not seem to cover the I/O path for XFS? I was unable to throttle processes reading from an XFS file system.
Also I think the name of the function cgroup_io_account is a bit too innocent? It sounds like a inline function "{ io += bytes; }", not like something which may sleep.
-- Carl Henrik
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