On Fri, Jan 19, 2001 at 10:20:23AM -0800, Rajagopal Ananthanarayanan wrote:
> There's been several mail exchanges already on this thread.
> Let me try to summarize:
> 1. The page cleaner should walk the dirty list of pages.
> 2. There are 2 reasons to start write-out earlier than on
> just memory pressure/aging information alone. (a) to minimize
> data lost due to delalloc pages not written to disk (b) to minimize
> write pressure on the disk .. you don't want to fill-up a 1GB system
> with delalloc pages & starting to write out at 20 MB/sec to disk.
(b) should be handled in a generic way (by the mm subsys), but I'm not
sure how to do (a).
> 3. Its almost tempting to make kswapd do the delalloc conversions,
> since it walks the inactive dirty list through page_launder().
> However, if you think about it, the conversion is an operation
> that logically sits between make a page delalloc & writing it out to
> disk. IMO, we need a seperate daemon to perform the conversions.
Agreed. Again it should be handled outside XFS, e.g. my generic kiobuf
address_space methods start using delayed allocation (in a hairy way ...).
Whip me. Beat me. Make me maintain AIX.