On Thu, 11 Sep 2008, Scott Carey wrote:
> Preliminary summary:
>
> readahead | 8 conc read rate | 1 conc read rate
> 49152 | 311 | 314
> 16384 | 312 | 312
> 12288 | 304 | 309
> 8192 | 292 |
> 4096 | 264 |
> 2048 | 211 |
> 1024 | 162 | 302
> 512 | 108 |
> 256 | 81 | 300
> 8 | 38 |
What io scheduler are you using? The anticipatory scheduler is meant to
prevent this slowdown with multiple concurrent reads.
Matthew
--
And the lexer will say "Oh look, there's a null string. Oooh, there's
another. And another.", and will fall over spectacularly when it realises
there are actually rather a lot.
- Computer Science Lecturer (edited)