Re: [PATCH 1/4] Add kswapd descriptor.

[KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>]

On Tue, 7 Dec 2010 12:29:29 +0530
Balbir Singh <balbir@linux.vnet.ibm.com> wrote:

> * KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> [2010-12-07 15:24:23]:
> > An argument to balance_pgdat_for_memcg() or a start point of zonelist[].
> > i.e.
> > 	zone_list = NODE_DATA(victim)->zonelist[0 or 1]
> > 
> > 	for_each_zone_zonelist(z, zone_list)....
> > 
> > But, this is just an example, we just need to determine where we reclaim
> > page from before start walking.
> >
> 
> OK, I understand. BTW, I am not against integration with kswapd for
> watermark based reclaim, the advantage I see is that as we balance
> zone/node watermarks, we also balance per memcg watermark. The cost
> would be proportional to the size of memcg's that have allocated from
> that zone/node. kswapd is not fast path and already optimized in terms
> of when to wake up, so it makes sense to reuse all of that. 
> 

But we cannot use balance_pgdat() as it is because we don't need almost
all checks in it and I don't want to add hooks into it because it's
updated frequently. And, I doubt how cleanly we can do merging.

As Ying Han did, adding balance_pgdat_for_memcg() is a clean way for now.
kswapd wakeup, sleep routine may be able to be reused.


Thanks,
-Kame

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>