[Imap-uw] Mix filesize
joel at panacea.null.org
Sun Sep 16 15:34:19 PDT 2007
> > If the variation in message size affects the choice of MIXDATAROLL, is it
> > possible that hitting a file size is the wrong constraint for rolling
> > out a new data file? Perhaps MIXDATAROLL should be a number of messages?
> Don't think so. This would lead to some files getting huge, and this
> wouldn't be any good for inremental backup performance.
The flip side is that with fewer messages in a file the probability of it
being hit with a modification (which, if I understand mix correctly, can
only be a delete once the file is "full") is significantly less, and so
it won't be backed up as often, if at all. With only one message in the
file, for instance, it is backed up exactly once.
> > Or perhaps the condition should be "max file size, max no. of messages,
> > whichever happens first"?
> This sounds more interesting. But from the statistics I posted
> yesterday, you can see that the number of messages per file is very low,
> so I don't think that adding a test for max number of messages would be
> any different from how it is today, at least not for our installation.
What I'm suggesting would involve a significantly larger max file size.
My instinct is that the file size is smaller than it should be because
it's doubling as an ad hoc max message number restriction.
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