Re: Online 7.12 Tunning [more info]

Hi! Just a question on your response: At 07:11 PM 9/22/97 EDT, Art Kagel wrote: > > [... snip ...] > >3) You have but one AIO VP, since the CPU VP does work for other threads >while waiting for the AIO VP to return many IO requests can queue up. >Informix recommends 1.5 AIO VPs per chunk for version after 7.20 and >2.5->3 AIO VPs for earlier ODS versions (the AIO code was rewritten in >7.20 and is much faster). With the 6 chunks you have you should >configure 15-18 AIO VPs (yes even on a single CPU machine) lean toward >15 if adding chunks is a rare thing and 18 if the database is growing. > In Elizabeth Suto's book INFORMIX-OnLine Performance Tuning, on pages 67-69, she addresses AIO VPs. If one has KAIO enabled, then one would only require a few AIO VPs to handle non-raw file I/O, such as to online.log or $ONCONFIG, as well as any cooked chunks. Has this changed in post ODS 7.20? I've lost the original message from Serafim, but I think he mentioned that he had KAIO turned on. Best regards, Nigel +-------------------------------------------------------------+ |Name : Edmund Nigel Gall Tel: (868) 636 3153 | |Title : Information Systems Specialist Fax: (868) 679 3770 | |Company: Process Plant Services Limited | |Address: Atlantic Avenue, Point Lisas Industrial Estate | | Point Lisas, Couva, Trinidad & Tobago, W.I. | +----- mailto:nigelg@ppsl.com ------ http://www.ppsl.com -----+