Re: Mirroring

Posted in 1994

Richard Ridley — 27 Oct 1994 01:13:08 -0400 — source: Informix-list mailing list archive (1991-1998)

Ti Lian Hwang writes: |We have a new HP9000 machine with 2 fast SCSI disks and 2 slower |disks. | |We are using informix mirroring on them. | |Is there advantages or disadvantages if the mirror copies are both |in the in the slow disks, or a mix of slow and fast disks ? | |I mean | | Disk A (slow) Disk B (slow) Disk C (fast) Disk D | (fast) |1) dbspace 1 dbspace 1 dbspace 2 dbspace 2 |2) dbspace 1 dbspace 2 dbspace 1 dbspace 2 | |Is option (1) or (2) more efficient ? I would say that it makes sense to speed up those dbspaces that are the busiest ie: the rootdbs, logical and physical log dbspaces, and any other dbspaces that are relatively busy. In other words, use both fast disks to mirror the dbspaces that are busiest - a variation of option 1. This should improve the response times for the majority of the transactions, rather than increase it by a lesser amount for all transactions. Regards, Richard Ridley DHL Asia Pacific Singapore