Luke Lonergan wrote:
Transfer rates:
outside: 102400 kbytes in 2.075984 sec = 49326 kbytes/sec
middle: 102400 kbytes in 2.100510 sec = 48750 kbytes/sec
inside: 102400 kbytes in 2.042313 sec = 50139 kbytes/sec
I have 6 ultra a320 72G 10k discs
Yah - ouch. With 6 drives in a RAID10, you should expect 3 drives worth of
sequential scan performance, or anywhere from 100MB/s to 180MB/s. You're
getting from half to 1/3 of the performance you'd get with a decent raid
controller.
If you add a simple SCSI adapter like the common LSI U320 adapter to your
DL380G3 and then run software RAID, you will get more than 150MB/s with less
CPU consumption. I'd also expect you'd get down to about 2ms access times.
This might not be easy for you to do, and you might prefer hardware RAID
adapters, but I don't have a recommendation for you there. I'd stay away
from the HP line.
This is my new postgreql 8.1.3 server, so i have many options (in fact,
any option) to choose from, i want maximum performance, if i undestood
you well, do you mean using something like vinum?
i forgot to mention that the 6 discs are in a MSA500 G2 external
storadge, additionally i have two 36G a320 10k in raid 10 for the os
installed in the server slots.
---
Miguel
