Re: mmap vs. O_DIRECT

Alan Cox
2004-11-10T23:23:29Z

On Mer, 2004-11-10 at 00:05, Bill Davidsen wrote:
> I have an application which does a lot of mmap to process its data. The
> huge waitio time makes me think that mmap isn't doing direct i/o even
> when things are alligned.

Make sure you are using MAP_SHARED in such cases so that the object you
have is the page cache object, also remember to use madvise