MTD/flash perfomance statistics

[Bruce_Leonard at selinc.com]

Hi Artem,

Artem Bityutskiy <dedekind at infradead.org> wrote on 11/11/2008 09:38:09 PM:

> On Tue, 2008-11-11 at 10:08 -0800, Bruce_Leonard at selinc.com wrote:
> > We're using UBIFS/UBI/MTD/NAND and we want to find out how much of our 

> > time is spent accessing the flash.  Are there any tools or is there 
any 
> > code in that chain that collects any sort of statistics on flash 
> > performace/utilization?  I could do something as crude as a counter in 
my 
> > NAND driver, but if there's anything more sophisticated that I can 
just 
> > "use out of the box" so to speak that would be better.  Thanks.
> 
> Not sure what exactly you need, but probably you want oprofile?
> 
> -- 
> Best regards,
> Artem Bityutskiy (Битюцкий Артём)
> 

I finally got the app guys to pin down exactly what they want.  Here's a 
copy of the email I got from them:

"They appear to be going the wrong way.  We're looking for runtime 
diagnostic-y type of things (i.e. Number of writes to the flash, number of 
bad blocks, statistics from the wear leveler to see how the wear leveling 
is going, etc.)  Things that don't take a lot of CPU time to do, like 
counters, that we can use to give us information on what a customer's box 
may or may not be doing in the field.  A ready example that comes to mind 
is ethernet statistics, bytes/packets sent/recieved, error counts, etc. Or 
if you want a storage analog, things like you would see in 
/sys/block/hda/stat but adapted to make sense in Flash storage."

Is there anything like that for UBIFS/UBI/MTD/NAND that you're aware of? 
Thanks.

BTW, we're happily up and running UBIFS on a 2GiB flash part with no 
errors.  Mount times are pretty resonable.  I don't have current times 
because I've been about three kernel versions ahead of everyone else so 
the stuff they've all been using until recently didn't have some of the 
speed improvments.  If I get the time (and remember to do it ;)  ) I'll 
try to float some numbers out there.

Thanks for all the help over the last several months getting my stuff 
going.  It's been great working with you.

Bruce