Re: Informix OnLine on RAID drives

Melody Fallah-Khair wrote: > > Hello, > > Has anybody experienced setting up Informix Online 7.x on > RAID (Redundant Array of Independent Disks) disk drives? Any performace > improvement or suggestion for how to set them up (RAID 0, 1, 2, ...6)? > > I'm wondering specially between using either Informix mirroring or > hardware mirroring provided by RAID 1. The I/O performance is an > important factor to us. > > Thanks Almost every paper I've read by those I respect advocate hardware mirroring in preference to RDBMS mirroring. At my site, we have recently moved to a RAID 1 configuration. This involves the use of shiny new hardware, with built-in disk cache, so it's not possible to compare directly with the "ordinary" disks we had before. But we've certainly not suffered performance deterioration. In my previous site, I used RAID 5 on our database servers (not Informix though). Again, performance was acceptable, but the drawbacks more subtle. In this configuration the logical uniys that you, the administrator, sees are actually striped over a number of physical units. thus the ordinary load balancing that you might try to do as a result of onstat -D output would be of no value, since the physical layout of the chunks in unknown. As to which RAID level to implement, doesn't this largely depend upon how much hardware you have available? Neil Truby Chase Manhattan Bank Bournemouth, UK