Re: Reducing checkpoint intervals...

Posted in 1998

Stefan Weideneder — Sun, 06 Sep 1998 11:34:11 +0100 — source: Informix-list mailing list archive (1991-1998)

Hi, in my opinion you must reduce LRU_MAX_DIRTY and LRU_MIN_DIRTY. It's not a good idea to reduce the time interval between the checkpoints because each checkpoint costs a lot of overhead ( thread-synchronisation and checkpoint-waits ). How about: http://www.weideneder.de/informix/faq/checkdur.html Your Checkpoint duration depends on: + the number of modified buffers in your buffer pool. (LRU_MAX_DIRTY ) + the number of concurrent threads while the checkpoint is requested + the number of CLEANERS and LRUS + the number of AIO-vp's that perform the I/O + how you spread your I/O across the disks + in which order you assigned your chunks to your dbspaces. Okay, I think that's it. Bye Stefan Weideneder