patched kernel： ============================================================================================================================ linux-g6ih:/home/sean/vfs_test # ./test_write.sh ./writetest 10 Blocks: 800 Seed: 1498036495 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Write: Success real 0m18.466s user 0m13.581s sys 0m4.116s aaa Blocks: 800 Seed: 1498036515 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Write: Success real 0m16.188s user 0m12.013s sys 0m3.924s aaa Blocks: 800 Seed: 1498036532 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Write: Success real 0m15.700s user 0m11.481s sys 0m3.708s aaa Blocks: 800 Seed: 1498036549 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Write: Success real 0m15.284s user 0m11.493s sys 0m3.656s aaa Blocks: 800 Seed: 1498036567 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Write: Success real 0m16.049s user 0m11.933s sys 0m3.608s aaa Blocks: 800 Seed: 1498036585 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Write: Success real 0m16.489s user 0m12.441s sys 0m3.612s aaa Blocks: 800 Seed: 1498036603 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Write: Success real 0m15.466s user 0m11.605s sys 0m3.552s aaa Blocks: 800 Seed: 1498036620 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Write: Success real 0m16.381s user 0m11.749s sys 0m3.832s aaa Blocks: 800 Seed: 1498036638 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Write: Success real 0m16.163s user 0m12.241s sys 0m3.736s aaa Blocks: 800 Seed: 1498036655 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Write: Success real 0m15.523s user 0m11.537s sys 0m3.480s aaa linux-g6ih:/home/sean/vfs_test # ./test_write.sh ./readtest 10 Blocks: 800 Seed: 1498036833 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Read: Success real 0m14.719s user 0m10.305s sys 0m3.036s aaa Blocks: 800 Seed: 1498036849 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Read: Success real 0m13.756s user 0m10.933s sys 0m2.568s aaa Blocks: 800 Seed: 1498036864 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Read: Success real 0m13.743s user 0m10.841s sys 0m2.544s aaa Blocks: 800 Seed: 1498036879 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Read: Success real 0m14.808s user 0m11.545s sys 0m2.752s aaa Blocks: 800 Seed: 1498036895 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Read: Success real 0m13.863s user 0m10.777s sys 0m2.684s aaa Blocks: 800 Seed: 1498036910 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Read: Success real 0m13.377s user 0m10.301s sys 0m2.856s aaa Blocks: 800 Seed: 1498036925 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Read: Success real 0m13.394s user 0m10.465s sys 0m2.576s aaa Blocks: 800 Seed: 1498036939 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Read: Success real 0m13.645s user 0m10.457s sys 0m2.968s aaa Blocks: 800 Seed: 1498036954 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Read: Success real 0m13.420s user 0m10.297s sys 0m2.560s aaa Blocks: 800 Seed: 1498036968 Output file: '/mnt/sdb1/fileout' Writing 800 blocks of 1048576 bytes to '/mnt/sdb1/fileout' Read: Success real 0m13.394s user 0m10.345s sys 0m2.752s aaa