Re: [patch] adjustments to dirty memory thresholds

[Andrew Morton <akpm@zip.com.au>]

Rik van Riel wrote:
> 
> On Wed, 28 Aug 2002, Andrew Morton wrote:
> 
> > But sigh.  Pointlessly scanning zillions of dirty pages and doing
> > nothing with them is dumb.  So much better to go for a FIFO snooze on a
> > per-zone waitqueue, be woken when some memory has been cleansed.
> 
> But not per-zone, since many (most?) allocations can be satisfied
> from multiple zones.  Guess what 2.4-rmap has had for ages ?

Per-classzone ;)

> Interested in a port for 2.5 on top of 2.5.32-mm2 ? ;)
> 
> [I'll mercilessly increase your patch queue since it doesn't show
> any sign of ever shrinking anyway]

Lack of patches is not a huge problem at present ;).  It's getting them
tested for performance, stability and general does-good-thingsness
which is the rate limiting step.

The next really significant design change in the queue is slablru,
and we'll need to let that sit in partial isolation for a while to
make sure that it's doing what we want it to do.

But yes, I'm interested in a port of the code, and in the description
of the problems which it solves, and how it solves them.  But what is
even more valuable than the code is a report of its before-and-after
effectiveness under a broad range of loads on a broad range of 
hardware.  That's the most time-consuming part...