On Mon, Dec 21, 2009 at 11:20 PM, Damien Katz <[email protected]> wrote:
> I saw recently some issues people where having with compaction, and I > thought I'd get some thoughts down about ways to improve the compaction > code/experience. > > > 5. Better Low level file driver support. Because we are using the Erlang > built-in file system drivers, we don't have access to a lot of flags. If we > had our own drivers, one option we'd like to use is to not OS cache the > reads and write during the compaction, it's unnecessary for compaction and > it could completely consume the cache with rarely accessed data, evicting > lots of recently used live data, greatly hurting performance of other > databases. > Related to this, I got a patch accepted for Erlang/OTP branch dev, which adds posix_fadvise to the file module: http://github.com/erlang/otp/commit/be2ebfd0f2b8e15363288d1dab4c177c237e234a In the long term we can possibly use it for CouchDB (with Erlang R14 something). > > Anyway, just getting these thoughts out. More ideas and especially code > welcome. > > -Damien -- Filipe David Manana, [email protected] "Reasonable men adapt themselves to the world. Unreasonable men adapt the world to themselves. That's why all progress depends on unreasonable men."
