On Thu, 6 Mar 2014 18:04:04 -0500 Johannes Weiner <hannes@xxxxxxxxxxx> wrote: > > what bug does it fix and what are the user-visible effects?? > > Ok, maybe this is better? > > --- > > GFP_THISNODE is for callers that implement their own clever fallback > to remote nodes. It restricts the allocation to the specified node > and does not invoke reclaim, assuming that the caller will take care > of it when the fallback fails, e.g. through a subsequent allocation > request without GFP_THISNODE set. > > However, many current GFP_THISNODE users only want the node exclusive > aspect of the flag, without actually implementing their own fallback > or triggering reclaim if necessary. This results in things like page > migration failing prematurely even when there is easily reclaimable > memory available, unless kswapd happens to be running already or a > concurrent allocation attempt triggers the necessary reclaim. > > Convert all callsites that don't implement their own fallback strategy > to __GFP_THISNODE. This restricts the allocation a single node too, > but at the same time allows the allocator to enter the slowpath, wake > kswapd, and invoke direct reclaim if necessary, to make the allocation > happen when memory is full. Looks good, thanks. I'll send this Linuswards next week. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>