performance woe's

[kris buggenhout <kris.buggenhout@xxxxxxxxx>]

Hi,

still doing iozone testing

I found that when U go out of the buffer cache ( in my case 128Meg) the performance drops ( as one would expect)
But surprinsingly writes are still a lot faster than reads when using XFS, this is kinda paradox ...
As the slowest operation for a disk is actually the write operation...
 

any idea's ?
 

snippet of the (preliminiary) results:

                                                            random  random    bkwd  record  stride
              KB  reclen   write rewrite    read    reread    read   write    read rewrite    read   fwrite frewrite   fread  freread

           65536      64  129422  160472   205958   207538  189159   92569  200343  300786  190322   116578   119016  197913   200438
           65536     128  137591  149548   189628   177738  186519   97034  188552  238659  188278    99012   108400  185875   180353

          131072      64   21390   14634     7161     7002    7663   26880    4544  317377    7253    14230    20834    7092     7156
          131072     128   21451   21038     6975     6984    8780   27774    4883  207294    6671    21400    17567    7240     7122