Re: Reducing checkpoints

PapaKiKi wrote: > Hi,i have a database with 80gigabytes of data with 360users and up to > 400 when at peak.I use IDS 7.31 running on HP-UX 11.0 and 8 Gig of > memory.The checkpoints get to as high as 58sec at peak periods .Users > often run out of connections into informix.How can i reduce these > checkpoints to acceptable levels like 3seconds.What others measures can > help me.Below is the configuration from the onconfig.live in informix <SNIP> Yow, you have lots of tuning opportunities in that ONCONFIG file. Just to address the 'Users often run out of connections' change the NETTYPE for ipcshm to: NETTYPE ipcshm,4,300,CPU As to the checkpoint duration, change: LRU_MAX_DIRTY 2 LRU_MIN_DIRTY 1 Using zero (0) for LRU_MIN_DIRTY often causes long checkpoints and beats on the IO subsystems mercilessly. Also consider upgrading to IDS 10.00 so you can use fractional values for the LRU_MIN/MAX_DIRTY settings. I strongly suspect that if all of your users are coming in as shared memory connections that the NETTYPE change will make a significant difference. Art S. Kagel