Re: Informix 7.x and RAID 5

Mike Flannery <flannery@informix.com> writes: >Well, after sending out my last piece of mail I received a few >letters commenting on my opinions. I apoligize if I made anyone >a little defensive or upset because of my views. I'm not (as my >letters may imply ;-) ) a RAID basher! RAID can be a very good >and cost effective alternative to mirroring. The point of my letters >was not to bash RAID or any vendor who develops or sells RAID >subsystems. My point was to let everyone see the potential >problems with using RAID with Informix OnLine fragmentation. It >will work but it's hard to guarentee where the data will end >up on subsystem when you fragment data that has already been >fragmented. There are many benifits to using Informix mirroring >and Informix fragmentation. Without mirroring you cannot get >split reads and without fragmentation you cannot get fragmentation >elimination. With RAID you can get a speedy (read) system and >one that's very easy to maintain (with DG you just flip a switch!) >and very fault tolerant. It's a trade off and one that should not >be taken lightly. >Mike >These are my opinions. Not my employer's or my friends'. Thanks for taking the trouble to prepare these postings. It should be pointed out that Storage Computer is the company with the longest experience in the RAID performance business, starting RAID performance R&D in 1984. (See RAID Museum at http://www.storage.com/ for pictures of those first RAIDs from 1984/5.) As a consequence of 11+ years of RAID performance R&D, the company has developed some very fast RAID architectures, much faster than the early RAID levels from the mid-80s. We have large numbers of big database users, including Oracle, Sybase, Informix, SAP, etc. Our big users refer to RAID 7 as a database accelerator. There are a number of these RAID 7 DB customer reference stories on the company's WWW server, http://www.storage.com/. Nevertheless, it might be very interesting indeed for Informix to officially measure the RAID 7 performance enhancements in different environments and publish some results. Let us know if Informix would like to proceed in this direction. Mike W. Michael Willett, EE mwillett@storage.com Storage Computer Corp. http://www.storage.com/ 11 Riverside Street Nashua, NH 03062 Tel. 603-880-3005 :::I/O-accelerated, very fast disk arrays for all SCSI systems to 1,000 GB:::