Ratio (bufwrites + pagreads)/buffwts

Dear Art, from the discussions in the iiug you seem to be a real expert on Informix problems. Therefore I'd like to ask you two questions: 1) you once wrote in the iiug that the number of buffwts should not exceed 7% of (bufwrites + pagreads), otherwise performance will suffer. I'm running IDS 7.30 UC6 on a k360/4 engine (hp-ux 10.20) with the following parameters: NUMCPUVPS=4, LRUS=8 (99% of LRUs are free LRUs) CLEANERS=8 BUFFERS=82000 read cache=98.86% write cache=96.04% checkpoint duration 5-10 secs. Informix Performance Guide (Version 7.3, Feb. 98) recommends for these parameters NUMCPUVPS = number of cpus in engine LRUS = CLEANERS ~ number of cpus (but can also be higher) BUFFERS = from 20 to 25% of phys. memory (in MB) that is in my case (100 MB phys. mem) 10000 - 12500. The performance guide, however, warns of allocating too many buffers (can lead to excess paging activity). What do you think about these recommandations? Will performance be improved increasing LRUS/CLEANERS and/or BUFFERS or should the least be decreased? 2) we're planning to migrate from AutoRaid (Raid5) to XP256. I've read the discussion in the iiug about this topic but as a real newbie in the field of Raids, I do not know, what exactly Raid10 means? thanks for help thomas ------------------------------------------------- Thomas Stainer - tstainer@styria.com