RAID controller settings

[objohn]

Hi all,
Does anyone have any views on what cache settings to apply to a RAID controller on a server running progress 8.3d for best performance?
Database is on a RAID 1 set, with 15K SCSI disks

On the Read Policy I can choose "read ahead", "adaptive read ahead" and "no read ahead"
Write policy options are: "write back" or "write through"
Cache : Direct I/o or Cache I/O

Many thanks for any help received,
Owen John

 

[Kopperton]

Write-back caching in Raid1 will give you better performance in IO throughput as data is said to be transfered to cache. But write-through is extremely (paranoid) safer in raid1 because waits acknowledgment for data to be written in both disks.

As for read policy in raid 1 read-ahead is enough. Adaptive read-ahead is good for raid 5 which is superior in read then raid1.

 

[objohn]

thank you for taking the time to respond.

OJ