Re: [PATCH 8/8] vmscan: Kick flusher threads to clean pages when reclaim is encountering dirty pages

Christoph Hellwig
2010-07-19T14:23:51Z

On Mon, Jul 19, 2010 at 02:11:30PM +0100, Mel Gorman wrote:
> + /*
> + * If reclaim is encountering dirty pages, it may be because
> + * dirty pages are reaching the end of the LRU even though
> + * the dirty_ratio may be satisified. In this case, wake
> + * flusher threads to pro-actively clean some pages
> + */
> + wakeup_flusher_threads(laptop_mode ? 0 : nr_dirty + nr_dirty / 2);
> +

Where is the laptop-mode magic coming from?

And btw, at least currently wakeup_flusher_threads writes back nr_pages
for each BDI, which might not be what you want. Then again probably
no caller wants it, but I don't see an easy way to fix it.