ARMでNILFS2を試す(スピードテスト)

NILFS 
# hdparm -tT /dev/sda5
/dev/sda5:
 Timing cached reads:   328 MB in  2.01 seconds = 163.18 MB/sec
 Timing buffered disk reads:  158 MB in  3.02 seconds =  52.32 MB/sec
 Timing cached reads:   328 MB in  2.01 seconds = 163.18 MB/sec
 Timing buffered disk reads:  172 MB in  3.02 seconds =  56.95 MB/sec
 Timing cached reads:   328 MB in  2.01 seconds = 163.18 MB/sec
 Timing buffered disk reads:  164 MB in  3.00 seconds =  54.67 MB/sec

# hdparm -tT /dev/sda6
/dev/sda6:
 Timing cached reads:   328 MB in  2.00 seconds = 164.00 MB/sec
 Timing buffered disk reads:  162 MB in  3.01 seconds =  53.82 MB/sec
 Timing cached reads:   328 MB in  1.99 seconds = 164.82 MB/sec
 Timing buffered disk reads:  160 MB in  3.00 seconds =  53.33 MB/sec
 Timing cached reads:   328 MB in  2.00 seconds = 164.00 MB/sec
 Timing buffered disk reads:  168 MB in  3.00 seconds =  56.00 MB/sec

パーティションのディスク内での位置的な速度差はなさそう。


ファイルを作ってみる。

OLP02:~# time dd if=/dev/zero of=/mnt/ext3/dd.text bs=1024 count=100000
100000+0 records in
100000+0 records out
102400000 bytes (102 MB) copied, 8.20721 seconds, 12.5 MB/s

real    0m8.376s
user    0m0.510s
sys     0m6.490s
OLP02:~# time dd if=/dev/zero of=/mnt/nilfs/dd.text bs=1024 count=100000
100000+0 records in
100000+0 records out
102400000 bytes (102 MB) copied, 12.7962 seconds, 8.0 MB/s

real    0m12.907s
user    0m0.430s
sys     0m7.680s

2/3くらい。
うーん、思ったより遅いかも...

bonnie++
Version  1.03 ------Sequential Output------ --Sequential Input- --Random-
              -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine  Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP  /sec %CP
ext3     300M  1610  96 25187  69 20892  66  1655  97 56280  66 234.2   4
nilfs2   300M  1511  91 10730  36  8164  23  1609  97 24110   3 229.7   4
              ------Sequential Create------ --------Random Create--------
              -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
        files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
ext3       16  4907  97 +++++ +++  7374  95  4950  97 +++++ +++  7393  94
nilfs2     16   318  97 +++++ +++ 13614  98   324  97 +++++ +++  1313  95

あー、これはかなり遅いですね...


dbenchでも試してみる。

procs    ext3      NILFS (MB/sec) 
001      22.1568   19.4522
010      18.4532   11.9914
100       9.84602  11.9412

遅めの傾向はおおむね同じか。