On Fri, 10 Dec 2010, Mel Gorman wrote:

> When kswapd wakes up, it reads its order and classzone from pgdat and
> calls balance_pgdat. While its awake, it potentially reclaimes at a high
> order and a low classzone index. This might have been a once-off that
> was not required by subsequent callers. However, because the pgdat
> values were not reset, they remain artifically high while
> balance_pgdat() is running and potentially kswapd enters a second
> unnecessary reclaim cycle. Reset the pgdat order and classzone index
> after reading.
> 
> Signed-off-by: Mel Gorman <mel@csn.ul.ie>
> Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>

Reviewed-by: Eric B Munson <emunson@mgebm.net>