On Sun, 2009-04-19 at 11:54 +0530, Amit Shah wrote: > On (Sat) Apr 18 2009 [09:28:21], Mike Galbraith wrote: > > Probably because you're swapping heavily, and that is perturbing your > > The variance only affects the 4k test; the other times more or less > remain the same. My box disagrees. (bumps ulimits to test 4BG... OS+swap live on sdb btw) ./test-file-zero-alloc-speed 4 /dev/sdf3 /media/root ext3 rw,_netdev,noatime,data=foo,acl,user_xattr foo=guarded 4k 225 141 80 142 361 8k 74 96 362 78 84 mm 55 57 57 57 57 foo=writeback 4k 179 264 187 125 93 8k 94 161 73 334 84 mm 57 58 57 56 57 foo=ordered 4k 81 74 76 80 75 8k 77 76 224 79 79 mm 59 56 60 58 59 foo=journal 4k 95 297 69 83 420 8k 73 139 158 80 78 mm 57 58 56 59 56 ./test-file-zero-alloc-speed 2 /dev/sdf3 /media/root ext3 rw,_netdev,noatime,data=foo,acl,user_xattr foo=guarded 4k 28 27 27 28 28 8k 28 27 27 28 27 foo=writeback 4k 27 27 27 27 27 8k 28 28 27 27 28 All journal modes seem subject to bad throughput under heavy pressure, though data=ordered seems much less likely to suffer for some reason. Major difference _seems_ to be that write()+largefile induces very much swap activity. -Mike -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
