>> going to the same drives. This turns your fast sequential I/O into
>> random I/O with the accompaning 10x or more performance decrease.
>>
>
> Unless you have a good RAID controller with battery-backed-up cache.
>
All right. :-) This is what I'll have:
Boxed Intel Server Board S5000PSLROMB with 8-port SAS ROMB card
(Supports 45nm processors (Harpertown and Wolfdale-DP)
Intel® RAID Activation key AXXRAK18E enables full intelligent SAS RAID
on S5000PAL, S5000PSL, SR4850HW4/M, SR6850HW4/M. RoHS Compliant.
512 MB 400MHz DDR2 ECC Registered CL3 DIMM Single Rank, x8(for
s5000pslromb)
6-drive SAS/SATA backplane with expander (requires 2 SAS ports) for
SC5400 and SC5299 (two pieces)
5410 Xeon 2.33 GHz/1333 FSB/12MB Dobozos , Passive cooling / 80W (2 pieces)
2048 MB 667MHz DDR2 ECC Fully Buffered CL5 DIMM Dual Rank, x8 (8 pieces)
SAS disks will be: 146.8 GB, SAS 3G,15000RPM, 16 MB cache (two pieces)
SATA disks will be: HDD Server SEAGATE Barracuda ES 7200.1
(320GB,16MB,SATA II-300) __(10 pieces)
I cannot spend more money on this computer, but since you are all
talking about battery back up, I'll try to get money from the management
and buy this:
Intel® RAID Smart Battery AXXRSBBU3, optional battery back up for use
with AXXRAK18E and SRCSAS144E. RoHS Complaint.
This server will also be an IMAP server, web server etc. so I'm 100%
sure that the SAS disks will be used for logging. I have two spare 200GB
SATA disks here in the office but they are cheap ones designed for
desktop computers. Is it okay to dedicate these disks for the WAL file
in RAID1? Will it improve performance? How much trouble would it cause
if the WAL file goes wrong? Should I just put the WAL file on the RAID
1+0 array?
Thanks,
Laszlo
