ufsstat - testers / feedback wanted!
Brian Candler
B.Candler at pobox.com
Fri Oct 14 09:46:42 PDT 2005
On Fri, Oct 14, 2005 at 11:20:02AM -0500, Eric Anderson wrote:
> For statistics gathering purposes though, should I worry about this, or
> go for 'fast and imperfect' instead of 'perfect and slow'? With
> filesystems, I think it's more important to leave performance high and
> get a notion of the statistics, rather than impact performance for
> perfect stats (that you may only look at occasionally anyhow).
Losing the odd count probably isn't a problem, but I think there's the
possibility of a badly wrong value if you're updating a 64-bit word in two
halves. For example, it might be possible to wrap around from
00000000ffffffff to 0000000000000000 instead of 0000000100000000.
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