On Fri, Jan 11, 2013 at 02:56:15PM +0900, Minchan Kim wrote: [...]
Ahh. You're talking about the shrinker interface. Yes, there is no way to tell if the freed memory will be actually "released" (and if not, then yes, we released it unnecessary).
I don't tell about actually "released" or not. I assume application actually release pages but the pages would be another zones, NOT targetted zone from kernel. In case of that, kernel could ask continuously until target zone has enough free memory.
[...]
isolate task to only some nodes/zones, if we really care about precise accounting?). But I'm surely open for ideas. :)
My dumb idea is only notify to user when reclaim is triggered by __GFP_HIGHMEM|__GFP_MOVABLE which is most gfp_t for application memory. :)
Ah, I see. Sure, that will help a lot. I'll try to incorporate this into the next iteration. But there are still unresolved accounting issues that I outlined, and I don't think that they are this easy to solve. :)
Thanks!
Anton