Re: [RFC patch 1/1] Track raid5/6 statistics.

[Jody McIntyre <scjody@sun.com>]

On Thu, Nov 27, 2008 at 06:15:35PM +0100, Gabor Gombas wrote:

> /proc contains a lot of legacy junk but nowadays the trend is that you
> should not add new files under /proc that are not process-related.

Agreed.  I'm not proposing that at all.

> Changing /proc/mdstat is IMHO out of question since it is part of the
> user visible ABI and breaking that is a big no-no. So if you want all
> info in a single file that pretty much leaves only debugfs.

AFAICT it was last changed on 2005-09-09 (appearing in 2.6.14).  This
suggests we can change it given a sufficiently good reason.

debugfs isn't a good idea since ordinary systems won't (or shouldn't)
have it mounted.  In case I wasn't clear: some of these statistics _are_
useful to administrators with sufficient RAID knowledge.  For example,
if "out of stripes" is large and you have lots of memory, increasing
stripe_cache_size will likely be useful.

Cheers,
Jody

> Gabor
> 
> -- 
>      ---------------------------------------------------------
>      MTA SZTAKI Computer and Automation Research Institute
>                 Hungarian Academy of Sciences
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