RE: Hitachi 7300 disk array ?

Well, let them burn there fingers. Perhaps if they need to save more money, they can go for no RAID and NT + no DB. Tell them RAID 5 was designed for Microdada use only. Comparing the 2 {or any} systems is not easy. How much cache ? Is the cache write back of write through ? Is it battery backed up ? What size disks ? More smaller disks are better. What RPM of disks. 15 000 RPM hope so {Yes all, new Seagate Cheetah 15X}. Seek Time ? {About 5 ms or faster} Is the disks the new ULTRA 160 {160 MB/s} transfer rate on the disks SCSI bus. How are the disks striped {number of disks per stripe set} What is the page size of the subsystem. {2K, 4, 8, 64, 128 }? Big is OK for file systems and smaller sizes OK for DB depending what type of data you are going to store. How many controllers to talk to sub system ? Are the controllers on different busses ? How many concurrent IO's can subsystem handle ?. How log to rebuild a failed RAID set ? What system will talk to subsystem ? {Hope not a single CPU system}. Do you know how to tune INFORMIX + OS? Are there enough CPU's and RAM in system. What I am generally saying is that any of us can take a !@#$% fast system and make it crawl depending on all of the above. Get the tech specialist of both systems an let them tune. Try to get real data with real load to do performance test. Hope it helps. Hannes Visagie Systems Engineer MIBCO -----Original Message----- From: michael martin [SMTP:michael_martin@komatsu.co.jp] Sent: Thursday, February 24, 2000 10:13 AM To: informix-list@iiug.org Subject: Hitachi 7300 disk array ? Hi listers, Sorry this is kinda off topic but it does include the dreaded words "RAID 5". Is anyone out there using a Hitachi 7300 series disk array subsystem ? My illustrious colleagues are "comparing" an EMC 5830 with the Hitachi 7300 but they seem to be committed to the Hitachi. And they are proposing to go with RAID 5 even though I have hit them over the head with one of Art Kagel's eloquent postings on why this is not a good idea. Anyway I would appreciate any comments/opinions/advice on the Hitachi 7300. TIA Michael michael_martin@komatsu.co.jp