> Can you check if the brute force patch below helps? Not sure if this helps at all, but here is the stack from all three processes involved. This is without MAP_POPULATE and with the patch you just sent. # ps aux | grep 'D[+]*[[:space:]]' USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND root 2314 0.2 0.0 0 0 ? D 19:44 0:00 [flush-8:0] root 2402 0.0 0.0 0 0 ? D 19:44 0:00 [xfssyncd/sda9] root 3861 2.6 9.9 16785280 4912848 pts/0 D+ 19:45 0:07 ./vmtest /xfs/hugefile.dat 17179869184 # for p in 2314 2402 3861; do echo $p; cat /proc/$p/stack; done 2314 [<ffffffff810d634a>] congestion_wait+0x7a/0x130 [<ffffffff8129721c>] kmem_alloc+0x6c/0xf0 [<ffffffff8127c07e>] xfs_inode_item_format+0x36e/0x3b0 [<ffffffff8128401f>] xfs_log_commit_cil+0x4f/0x3b0 [<ffffffff8128ff31>] _xfs_trans_commit+0x1f1/0x2b0 [<ffffffff8127c716>] xfs_iomap_write_allocate+0x1a6/0x340 [<ffffffff81298883>] xfs_map_blocks+0x193/0x2c0 [<ffffffff812992fa>] xfs_vm_writepage+0x1ca/0x520 [<ffffffff810c4bd2>] __writepage+0x12/0x40 [<ffffffff810c53dd>] write_cache_pages+0x1dd/0x4f0 [<ffffffff810c573c>] generic_writepages+0x4c/0x70 [<ffffffff812986b8>] xfs_vm_writepages+0x58/0x70 [<ffffffff810c577c>] do_writepages+0x1c/0x40 [<ffffffff811247d1>] writeback_single_inode+0xf1/0x240 [<ffffffff81124edd>] writeback_sb_inodes+0xdd/0x1b0 [<ffffffff81125966>] writeback_inodes_wb+0x76/0x160 [<ffffffff81125d93>] wb_writeback+0x343/0x550 [<ffffffff81126126>] wb_do_writeback+0x186/0x2e0 [<ffffffff81126342>] bdi_writeback_thread+0xc2/0x310 [<ffffffff81067846>] kthread+0x96/0xa0 [<ffffffff8165a414>] kernel_thread_helper+0x4/0x10 [<ffffffffffffffff>] 0xffffffffffffffff 2402 [<ffffffff8106d0ec>] down+0x3c/0x50 [<ffffffff8129a7bd>] xfs_buf_lock+0x5d/0x170 [<ffffffff8128a87d>] xfs_getsb+0x1d/0x50 [<ffffffff81291bcf>] xfs_trans_getsb+0x5f/0x150 [<ffffffff8128b80e>] xfs_mod_sb+0x4e/0xe0 [<ffffffff81271dbf>] xfs_fs_log_dummy+0x4f/0x90 [<ffffffff812a61c1>] xfs_sync_worker+0x81/0x90 [<ffffffff812a6092>] xfssyncd+0x172/0x220 [<ffffffff81067846>] kthread+0x96/0xa0 [<ffffffff8165a414>] kernel_thread_helper+0x4/0x10 [<ffffffffffffffff>] 0xffffffffffffffff 3861 [<ffffffff812ec744>] call_rwsem_down_read_failed+0x14/0x30 [<ffffffff812754dd>] xfs_ilock+0x9d/0x110 [<ffffffff8127556e>] xfs_ilock_map_shared+0x1e/0x50 [<ffffffff81297c45>] __xfs_get_blocks+0xc5/0x4e0 [<ffffffff8129808c>] xfs_get_blocks+0xc/0x10 [<ffffffff81135ca2>] do_mpage_readpage+0x462/0x660 [<ffffffff81135eea>] mpage_readpage+0x4a/0x60 [<ffffffff812986e3>] xfs_vm_readpage+0x13/0x20 [<ffffffff810bd150>] filemap_fault+0x2d0/0x4e0 [<ffffffff810db0a0>] __do_fault+0x50/0x4f0 [<ffffffff810db85e>] handle_pte_fault+0x7e/0xc90 [<ffffffff810ddbf8>] handle_mm_fault+0x138/0x230 [<ffffffff8102b37c>] do_page_fault+0x12c/0x420 [<ffffffff81658fcf>] page_fault+0x1f/0x30 [<ffffffffffffffff>] 0xffffffffffffffff -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href