Only in 2.4.9aa2: 00_megaraid-paranoid-1 Possibly it's a bug in the anti-bounce buffer patch but make sure the megaraid gets not confused by the fact I'm really allowing it to get the 512k large requests with the sd-max_sectors patch (in mainline the line I #ifdeffed out are meaningless so it never got tested). Only in 2.4.9aa1: 00_o_direct-13 Only in 2.4.9aa2: 00_o_direct-14 Janet Morgan promptly noticed I needed to s/>=/</ (it was an editing error while preparing the -13 patch). Only in 2.4.9aa1: 00_poll-nfds-1 Only in 2.4.9aa2: 00_poll-nfds-2 Fixed off by one check. Only in 2.4.9aa1: 40_blkdev-pagecache-13 Only in 2.4.9aa2: 40_blkdev-pagecache-14 Rediffed against o_direct-14. Only in 2.4.9aa1: 70_mmap-rb-3 Only in 2.4.9aa2: 70_mmap-rb-4 Fixed severe bug that caused mm corruption and crashes. (splitted a __vma_link_file off __vma_link_rb, build_mmap_rb must not mess with anything but the rb itself) Improved other bits to cover all the merging cases and some minor optimization. Since I couldn't find other issues in my workloads I'd now ask everybody who complained about the lack of vma merging in 2.4 to test this patch on their systems and to report the performance difference while running their vma intensive applications. Thanks! You don't need to use the -aa tree to test this patch, I ported it on top of 2.4.9 vanilla too, you can find it here: ftp://ftp.kernel.org/pub/linux/kernel/people/andrea/patches/v2.4/2.4.9/mmap-rb-4