On Wed, Jul 29, 2015 at 12:55:54PM +0200, Daniel Vetter wrote: > On Wed, Jul 29, 2015 at 11:49:45AM +0100, Mel Gorman wrote: > > On Mon, Jul 13, 2015 at 05:35:15PM +0900, Gioh Kim wrote: > > > My ARM-based platform occured severe fragmentation problem after long-term > > > (several days) test. Sometimes even order-3 page allocation failed. It has > > > memory size 512MB ~ 1024MB. 30% ~ 40% memory is consumed for graphic processing > > > and 20~30 memory is reserved for zram. > > > > > > > The primary motivation of this series is to reduce fragmentation by allowing > > more kernel pages to be moved. Conceptually that is a worthwhile goal but > > there should be at least one major in-kernel user and while balloon > > pages were a good starting point, I think we really need to see what the > > zram changes look like at the same time. > > I think gpu drivers really would be the perfect candidate for compacting > kernel page allocations. And this also seems the primary motivation for > this patch series, so I think that's really what we should use to judge > these patches. > > Of course then there's the seemingly eternal chicken/egg problem of > upstream gpu drivers for SoCs :( I recognised that the driver he had modified was not an in-tree user so it did not really help the review or the design. I did not think it was very fair to ask that an in-tree GPU driver be converted when it would not help the embedded platform of interest. Converting zram is both a useful illustration of the aops requirements and is expected to be beneficial on the embedded platform. Now, if a GPU driver author was willing to convert theirs as an example then that would be useful! -- Mel Gorman SUSE Labs -- 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>