Re: Fragments or RAID 5?

Bashar, Fragmenting with Round Robin buys you little unless you are using PDQ for DSS style queries. Even then, structured fragmentation plans are better. RAID5 is intended to provide data protection - not performance. RAID5 does stripe the data across the drives, it also maintains a checksum of the data. If you have 5 2GB drives, you will net 8 GB of usable space with RAID5 due to the 20% reserved for checksum. I don't personally believe Informix would see much benefit from either option you mentioned. It might even get worse. Look at RAID5 for high availability data protection. Also look at Informix mirroring. On the performance side, look at fragmenting by range (best where applicable), or expression (better than Round Robin). Hope it helps, Chuck ---- Chuck Ludwigsen <cludwigs@hotmail.com> Sr. Engineer, Summit Data Group <chuckl@summitdata.com> President - Memphis Informix Usr Grp <miug@hotmail.com> ** My opinions are my own and sometimes conflict with those of my employer ** Bashar Chalabi <bashar@ctl.com> wrote > Hi everybody, > > Anybody out there knows which provides the best performance: fragmenting > tables (round robin) on multiple hard drives or letting a RAID5 controller > do the work? > > Our hardware is a quad-processor Pentium Pro under SCO Unix, with 5 x 2GB > disks. Informix is ODS 7.22 > > Thanks for any input > > Bashar Chalabi > Card Tech Limited, London >