Re: Side Effects of Setting Tables Memory Resident

Dave Thacker wrote: > > In an effort to cut down on disk I/0, I have set 8 of our most heavily used > tables to memory resident. The checkpoints have gone through the roof. I > was averaging 1-3 seconds and am now stuck at 8-9, with spikes to 15. > Checkpoint interval is 300 seconds. onstat -F says: > > Fg Writes LRU Writes Chunk Writes > 517 130130 384588 > > So it appears that the page cleaners are not working well enough. > MAX_DIRTY is set to 2, MIN_DIRTY set to 1, so they ought to be working all > the time. No, they will stop with 1% buffers dirty. They will be working all the time if you set MAX_DIRTY to 1 and MIN_DIRTY to 0. Do you have enough page cleaners? Cheers, -- Mark. +----------------------------------------------------------+-----------+ | Mark D. Stock mailto:mdstock@mydas.freeserve.co.uk |//////// /| | http://www.informix.com http://www.informixhandbook.com |///// / //| | http://www.iiug.org +-----------------------------------+//// / ///| | |This email will self-destruct in |/// / ////| | |10 sec. If you received this email |// / /////| | |in error, sorry about the mess. |/ ////////| +----------------------+-----------------------------------+-----------+