From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 9 Jul 2007 12:04:57 +0100 Subject: Re: zone movable patches comments Message-ID: <20070709110457.GB9305@skynet.ie> References: <4691E8D1.4030507@yahoo.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <4691E8D1.4030507@yahoo.com.au> From: mel@skynet.ie (Mel Gorman) Sender: owner-linux-mm@kvack.org Return-Path: To: Nick Piggin Cc: Linux Memory Management , Andrew Morton List-ID: On (09/07/07 17:50), Nick Piggin didst pronounce: > Hi Mel, > > Just had a bit of a look at the zone movable stuff in -mm... Great. > Firstly, > would it be possible to list all the dependant patches in that set, or > is it just those few that are contiguous in Andrew's series file? > add-__gfp_movable-for-callers-to-flag-allocations-from-high-memory-that-may-be-migrated.patch and the few that are contiguous. I'm beginning to test with the following series file add-__gfp_movable-for-callers-to-flag-allocations-from-high-memory-that-may-be-migrated.patch create-the-zone_movable-zone.patch create-the-zone_movable-zone-fix.patch create-the-zone_movable-zone-fix-2.patch allow-huge-page-allocations-to-use-gfp_high_movable.patch allow-huge-page-allocations-to-use-gfp_high_movable-fix.patch allow-huge-page-allocations-to-use-gfp_high_movable-fix-2.patch allow-huge-page-allocations-to-use-gfp_high_movable-fix-3.patch handle-kernelcore=-generic.patch handle-kernelcore=-generic-fix.patch There was a minor reject in add-__gfp_movable-for-callers-to-flag-allocations-from-high-memory-that-may-be-migrated.patch but otherwise applied smoothly. > A few comments -- can it be made configurable? I guess there is not > much overhead if the zone is not populated, but there has been a fair > bit of work towards taking out unneeded zones. > It could be made configurable as zone_type already has configurable zones. However, as it is that would always be set on distro kernels for CONFIG_HUGETLB_PAGE, is there any point? It might make sense for embedded systems but I've received pushback from Andrew before for trying to introduce config options that affect the allocator before. > Also, I don't really like the name kernelcore= to specify mem-sizeof > movable zone. Could it be renamed and stated in the positive, like > movable_mem= or reserve_movable_mem=? It could but it was named this way for a reason. It was more important that the administrator get the amount of memory for non-movable allocations correct than movable allocations. If the size of ZONE_MOVABLE is wrong, the hugepage pool may not be able to grow as large as desired. If the size of memory usable of non-movable allocations is wrong, it's worse. > And can that option be written > up in Documentation? > Documentation/kernel-parameters.txt > What is the status of these patches? Are they working and pretty well > ready to be merged for 2.6.23? > I have not encountered problems with them in a long time. I'm re-testing now using 2.6.22 as a baseline but I believe they are ready for merging to 2.6.23. Thanks -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org