Hi, We're building a box to run two postfix instances to receive and send high volume of emails. According to the documentation it's better to run the two instances on separate disks for performance reason. I'm trying to understand how exactly does the disk I/O affect the postfix performance? By speed (bytes per second) or activities (# of read/write per second)?
Let's say I have two hard disks. If I make a RAID0 array out of the two disks the overall speed is twice as the speed of a single drive (I know it's not exact twice the speed. just simplify it for discussion). If the postfix performance depends on the disk speed then running two instances on two separate disks or running two instances on one RAID0 array should not make big difference, right? But if it depends on disk activities then running on two separate disks is definitely better. I know no matter which case using two disks is the choice. But if I have other reason to use RAID0 I just want to know how much performance I lost in postfix? Thanks -Irvin
