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Re: Re: Re: Please help me to evaluate flash/ssd life using vmstat -d

On Sat, 2011-02-05 at 19:10 -0600, R. Ramesh wrote:
> So what does vmstat -d tell me? Is the number of IO under "total" column 
> supposed to be the number of IOs
> issued to the controller with each IO being contiguous N sectors?

"man vmstat" says 'total' is "Total writes completed successfully".

Vmstat shows the same numbers as "cat /sys/block/sda/stat" (presumably
where it gets them from) and a copy of the linux documentation for this
is at http://www.mjmwired.net/kernel/Documentation/block/stat.txt

So yes, it looks like 'total' is the number of contiguous blocks of read
or writes. (Though they may not be contiguous once they get onto NAND.)
And 'sectors' the total size of all data read or written.

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