Re: [PATCH] [RFC] Throttle swappiness for interactive tasks

From: Abhijit Bhopatkar
Date: Thu Apr 19 2007 - 01:23:02 EST


> I just wanted to know weather its worth going forward or we have
> better reasons to discount any such direction?

The reason that the wrong pages get swapped out sometimes
could be due to a side effect of the way the swappiness
policy is implemented.

While the VM only reclaims page cache pages, it will still
rotate through the anonymous pages on the LRU list, which
effectively randomizes the order of those pages on the list.

In my mind i find it fundamentally wrong to separate anon pages from
page cache. It should rather be lot more dependent on which task
accessed them last. Although it seems due to some twisted relationships
bet anon pages and interactive tasks separating them improves it.
Am i missing something here?

I need to get back to benchmarking my patch to split the
lists - anonymous and other swap backed pages on one set
of pageout lists, filesystem backed pages on another list.
<snip>
Unfortunately my main desktop system at home depends on
Xen, so it's not as easy to use that patch there :(


Can you send me those patches please or point me to where i can find those?

Abhijit
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/