On Fri, Mar 27, 2009 at 5:14 PM, Jeff Garzik <jeff@xxxxxxxxxx> wrote: > Theodore Tso wrote: >> OTOH, the really big databases will tend to use direct I/O, so they >> won't be dirtying the page cache anyway. So maybe it's not worth the > > Not necessarily... From what I understand, a lot of the individual > low-level components in cloud storage, such as GoogleFS's chunk server[1] do > not bypass the page cache, even though they do care about the details of > data caching and data consistency. PostgreSQL does not use direct I/O, either (except for the write-ahead-logs which are written sequentially and only get read during database recovery). I'm sure that most of MySQL's database engines, also don't. -Dave -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
