Re: fadvise WILLNEED for tokyocabinet header cache
Hi,
* Andrea Arcangeli wrote:
> What if I can guarantee you that I don't modify the 'cur' directory
> under 'mutt'.
Ah, that reminds me of something. The hcache isn't updated when you
append a message to a cached folder. That would need to be done first.
Btw, I've made a patch more suitable for inclusion:
http://bitbucket.org/pdmef/muttpdmefmq/src/tip/patch-1.5.20hg.pdmef.fadvise.1
I'm not really sure about things: the order in which data will be
accessed (I don't think we should make any assumptions about it though
we always read and write data in inode order) and so I added the
POSIX_FADV_RANDOM flag. Second, I think it's micro-optimization to make
the size configureable. Though one could argue that we do that with
specifying the page size for gdbm/db4 already, I think it should still
work using the file's size. If not, and keeping in mind that we possibly
append to it, maybe we can get use 1.05*size or something.
Rocco