On Tue, 15 Nov 2005, YAMAMOTO Takashi wrote:
> a quick benchmark (bonnie++ -n0) is attached.
> *1 and *2 are the same kernel.  i did the same test twice.
> i'm wondering why "Rewrite" value has been changed.


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
base1          300M 10127  73 13784  80  6705  36 11810  73 18691  52  54.1 3
base2          300M 11062  82 11271  63  6431  34 11259  70 17904  49  53.6 3
readadead1     300M 10790  79 14023  79  8726  46 13632  80 20250  53  69.4 3
readahead2     300M  8699  63 14001  79  8670  45 13474  80 19970  51  69.5 3


This looks pretty good!
Can you explain how readahead influences the random seeks/sec of 
~54 -> 69? is it because the readin's not that random at all?


  - Hubert