On Fri, 2007-09-28 at 11:20 -0700, Christoph Lameter wrote: > > start 2 processes that each mmap a separate 64M file, and which does > > sequential writes on them. start a 3th process that does the same with > > 64M anonymous. > > > > wait for a while, and you'll see order=1 failures. > > Really? That means we can no longer even allocate stacks for forking. > > Its surprising that neither lumpy reclaim nor the mobility patches can > deal with it? Lumpy reclaim should be able to free neighboring pages to > avoid the order 1 failure unless there are lots of pinned pages. > > I guess then that lots of pages are pinned through I/O? memory got massively fragemented, as anti-frag gets easily defeated. setting min_free_kbytes to 12M does seem to solve it - it forces 2 max order blocks to stay available, so we don't mix types. however 12M on 128M is rather a lot. its still on my todo list to look at it further.. - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
