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