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Re: fadvise WILLNEED for tokyocabinet header cache



Hi,

* Andrea Arcangeli wrote:

> If there is interest I can do both
> changes myself and repost a proper patch, this is a local hack for
> myself so far.

I think making it faster is always good. However, there're some more 
points that would have to be solved to get the patch ready for 
inclusion. For example test if posix_fadvise() is available, why only 
do that for tokyocabinet, etc. Note that we're in a feature-freeze to 
prepare for 1.6, so no need to hurry if you want to make those changes.

> On a side note, a next step for further optimization, would be to
> eliminate the seeking low-disk-bandwidth getdents/readdir on the very
> large 'cur' directory, I'm unsure why there's that getdents and why
> running a getdents on the tiny 'new' directory (plus of course reading
> the header cache representing the 'cur' directory but at >30m/sec with
> below patch) isn't enough.

It's there because mutt displays what the mailbox has, not what the 
cache has. The cur/ directory may change greatly between to mutt 
sessions (e.g. a sync using unison, rsync, etc). I can't imagine 
dropping it (except for a replacement mechanism that tells us what files 
there are).

Rocco