| 1 |
Dear All, |
| 2 |
|
| 3 |
I have a server running Gentoo X64 2.6.27-gentoo-r8 with an Adaptec |
| 4 |
2820SA configured with a simple mirror. This card is a PCI-X card but due |
| 5 |
to an oversight on my part is plugged into a standard PCI slot on a PCI-E |
| 6 |
motherboard. |
| 7 |
|
| 8 |
Still, I'm getting some absolutely atrocious disk performance from it, a |
| 9 |
lot less than I would expect. Bonnie++ results are here: |
| 10 |
|
| 11 |
Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP |
| 12 |
/sec %CP |
| 13 |
aurora 2G 150 99 11141 6 6969 2 1482 94 20763 3 |
| 14 |
137.7 3 |
| 15 |
Latency 66612us 3997ms 2408ms 115ms 423ms |
| 16 |
739ms |
| 17 |
Version 1.93c ------Sequential Create------ --------Random |
| 18 |
Create-------- |
| 19 |
aurora -Create-- --Read--- -Delete-- -Create-- --Read--- |
| 20 |
-Delete-- |
| 21 |
files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP |
| 22 |
/sec %CP |
| 23 |
16 11022 64 +++++ +++ 14496 86 11836 65 +++++ +++ |
| 24 |
15375 96 |
| 25 |
Latency 34229us 62us 18737us 33868us 2540us |
| 26 |
21216us |
| 27 |
|
| 28 |
11 MB/s seems a bit rubbish compared to my bog standard Xeon with onboard |
| 29 |
sata which reports an easy 40MB/s on a single disk! |
| 30 |
|
| 31 |
All partitions are Reiser3, mounted with noatime and notail, which I am |
| 32 |
given to believe should lead to better performance. The driver is the |
| 33 |
standard Linux aacraid, compiled into kernel rather than as a module. |
| 34 |
|
| 35 |
Does anybody have any suggestions as to how I might improve performance? |
| 36 |
I'm hoping somebody replies with 'did you enable the aac turbo option in |
| 37 |
make menuconfig' or similar, but I suspect it will end up being more |
| 38 |
complicated than that. |
| 39 |
|
| 40 |
Cheers, |
| 41 |
Paul |
Archives