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-- These tests conducted on a laptop --
1st run, with only posix-fallocate on ext3
$ ./test-file-zero-speed
seconds:microseconds: 1235557175:156446
seconds:microseconds: 1235557212:186703
-------------------------------------------------------------------
2nd run, same program as above
$ ./test-file-zero-speed
seconds:microseconds: 1235557363:187840
seconds:microseconds: 1235557396:43475
-------------------------------------------------------------------
3rd run, same program (with no printf between gtod() and actual call)
$ ./test-file-zero-speed
posix-fallocate run time:
seconds:microseconds: 1235558782:292459
seconds:microseconds: 1235558816:331028
(approx 34s)
$ sudo filefrag ../tmp/10gfile-pf
../tmp/10gfile-pf: 134 extents found, perfection would be 9 extents
-------------------------------------------------------------------
With all three:
$ ./test-file-zero-speed
posix-fallocate run time:
seconds:microseconds: 1235569716:953548
seconds:microseconds: 1235569749:595276
(approx 33s)
mmap run time:
seconds:microseconds: 1235569749:595577
seconds:microseconds: 1235569789:622942
(approx 40s)
4096-sized chunk run time:
seconds:microseconds: 1235569791:134534
seconds:microseconds: 1235569839:132586
(approx 48s)
$ sudo filefrag ../tmp/*
../tmp/file-chunk: 57 extents found, perfection would be 9 extents
../tmp/file-mmap: 106 extents found, perfection would be 9 extents
../tmp/file-pf: 132 extents found, perfection would be 9 extents
-------------------------------------------------------------------
Added free(), 8k-chunk, close(fd) in time calculation
$ free -m
total used free shared buffers cached
Mem: 1954 859 1095 0 7 388
-/+ buffers/cache: 462 1491
Swap: 4094 742 3351
$ ./test-file-zero-speed
posix-fallocate run time:
seconds:microseconds: 1235571071:797642
seconds:microseconds: 1235571104:428998
(approx 33s)
mmap run time:
seconds:microseconds: 1235571104:429523
seconds:microseconds: 1235571147:770146
(approx 43s)
4096-sized chunk run time:
seconds:microseconds: 1235571149:318119
seconds:microseconds: 1235571187:731919
(approx 38s)
8192-sized chunk run time:
seconds:microseconds: 1235571189:614692
seconds:microseconds: 1235571228:355714
(approx 39s)
$ free -m
total used free shared buffers cached
Mem: 1954 853 1101 0 1 415
-/+ buffers/cache: 436 1517
Swap: 4094 742 3351
$ sudo filefrag ../tmp/*
[sudo] password for amit:
../tmp/file-chunk4: 60 extents found, perfection would be 9 extents
../tmp/file-chunk8: 86 extents found, perfection would be 9 extents
../tmp/file-mmap: 117 extents found, perfection would be 9 extents
../tmp/file-pf: 133 extents found, perfection would be 9 extents
-------------------------------------------------------------------
-- These tests conducted on a desktop --
$ sudo ./test-file-zero-speed /mnt/btrfs/
posix-fallocate run time:
seconds:microseconds: 1235757533:559903
seconds:microseconds: 1235757533:560119
(approx 0s)
mmap run time:
seconds:microseconds: 1235757533:564220
seconds:microseconds: 1235757551:589402
(approx 18s)
4096-sized chunk run time:
seconds:microseconds: 1235757552:688346
seconds:microseconds: 1235757572:585343
(approx 20s)
8192-sized chunk run time:
seconds:microseconds: 1235757576:143821
seconds:microseconds: 1235757592:424030
(approx 16s)
-------------------------------------------------------------------
sudo ./test-file-zero-speed /mnt/ext4/
posix-fallocate run time:
seconds:microseconds: 1235757627:972541
seconds:microseconds: 1235757642:159940
(approx 15s)
mmap run time:
seconds:microseconds: 1235757643:901565
seconds:microseconds: 1235757646:690830
(approx 3s)
4096-sized chunk run time:
seconds:microseconds: 1235757647:879737
seconds:microseconds: 1235757668:701027
(approx 21s)
8192-sized chunk run time:
seconds:microseconds: 1235757670:722389
seconds:microseconds: 1235757686:780528
(approx 16s)
-------------------------------------------------------------------
[ Extents were not enabled]
$ sudo ./test-file-zero-alloc-speed /mnt/ext4
posix-fallocate run time:
seconds:microseconds: 1235977123:542643
seconds:microseconds: 1235977137:673307
(approx 14s)
mmap run time:
seconds:microseconds: 1235977137:673494
seconds:microseconds: 1235977154:435404
(approx 17s)
4096-sized chunk run time:
seconds:microseconds: 1235977155:826068
seconds:microseconds: 1235977173:98883
(approx 18s)
8192-sized chunk run time:
seconds:microseconds: 1235977174:91821
seconds:microseconds: 1235977190:862035
(approx 16s)
$ sudo filefrag /mnt/ext4/*
/mnt/ext4/file-chunk4: 292 extents found, perfection would be 9 extents
/mnt/ext4/file-chunk8: 282 extents found, perfection would be 9 extents
/mnt/ext4/file-mmap: 295 extents found, perfection would be 9 extents
/mnt/ext4/file-pf: 279 extents found, perfection would be 9 extents
-------------------------------------------------------------------
[After enabling extents]
$ sudo ./test-file-zero-alloc-speed /mnt/ext4
posix-fallocate run time:
seconds:microseconds: 1235979104:790662
seconds:microseconds: 1235979104:848372
(approx 0s)
mmap run time:
seconds:microseconds: 1235979105:33407
seconds:microseconds: 1235979118:535711
(approx 13s)
4096-sized chunk run time:
seconds:microseconds: 1235979120:297221
seconds:microseconds: 1235979135:520910
(approx 15s)
8192-sized chunk run time:
seconds:microseconds: 1235979135:639915
seconds:microseconds: 1235979153:502270
(approx 18s)
$ sudo filefrag /mnt/ext4/*
File is stored in extents format
/mnt/ext4/file-chunk4: 29 extents found
File is stored in extents format
/mnt/ext4/file-chunk8: 20 extents found
File is stored in extents format
/mnt/ext4/file-mmap: 38 extents found
File is stored in extents format
/mnt/ext4/file-pf: 1 extent found
-------------------------------------------------------------------
$ sudo ./test-file-zero-alloc-speed /mnt/xfs/
posix-fallocate run time:
seconds:microseconds: 1235977241:411119
seconds:microseconds: 1235977241:469611
(approx 0s)
mmap run time:
seconds:microseconds: 1235977241:469981
seconds:microseconds: 1235977255:687663
(approx 14s)
4096-sized chunk run time:
seconds:microseconds: 1235977256:603450
seconds:microseconds: 1235977274:549963
(approx 18s)
8192-sized chunk run time:
seconds:microseconds: 1235977274:649325
seconds:microseconds: 1235977293:365759
(approx 19s)
$ sudo filefrag /mnt/xfs/*
/mnt/xfs/file-chunk4: 3 extents found
/mnt/xfs/file-chunk8: 4 extents found
/mnt/xfs/file-mmap: 2 extents found
/mnt/xfs/file-pf: 1 extent found
-------------------------------------------------------------------
$ sudo ./test-file-zero-alloc-speed /mnt/ext3/
posix-fallocate run time:
seconds:microseconds: 1235977308:469496
seconds:microseconds: 1235977326:366806
(approx 18s)
mmap run time:
seconds:microseconds: 1235977326:367325
seconds:microseconds: 1235977346:260276
(approx 20s)
4096-sized chunk run time:
seconds:microseconds: 1235977347:161513
seconds:microseconds: 1235977369:771397
(approx 22s)
8192-sized chunk run time:
seconds:microseconds: 1235977369:865221
seconds:microseconds: 1235977393:23403
(approx 24s)
$ sudo filefrag /mnt/ext3/*
/mnt/ext3/file-chunk4: 38 extents found, perfection would be 9 extents
/mnt/ext3/file-chunk8: 9 extents found
/mnt/ext3/file-mmap: 44 extents found, perfection would be 9 extents
/mnt/ext3/file-pf: 9 extents found
-------------------------------------------------------------------
$ sudo ./test-file-zero-alloc-speed /mnt/btrfs/
posix-fallocate run time:
seconds:microseconds: 1235977416:649716
seconds:microseconds: 1235977416:650009
(approx 0s)
mmap run time:
seconds:microseconds: 1235977416:650118
seconds:microseconds: 1235977434:626664
(approx 18s)
4096-sized chunk run time:
seconds:microseconds: 1235977435:634000
seconds:microseconds: 1235977452:208026
(approx 17s)
8192-sized chunk run time:
seconds:microseconds: 1235977452:294473
seconds:microseconds: 1235977471:143672
(approx 19s)
$ sudo /mnt/btrfs/*
FIBMAP: Invalid argument
...
-------------------------------------------------------------------
-------------------------------------------------------------------
|
