Re: IDS 10 disk configuration

On Tue, 2 Aug 2005 23:42:41 +0100, "Neil Truby" <neil.truby@ardenta.com> wrote: >"Art S. Kagel" <kagel@bloomberg.net> wrote in message >news:42EFD602.60800@bloomberg.net... >> david@smooth1.co.uk wrote: >>> At checkpoint time chunks are assigned round robin to page cleaners for >>> cleaning. >>> >>> ONE CHUNK WILL ONE GET ONE PAGE CLEANERS FLUSHING IT'S >>> WRITES AT CHECKPOINT TIME. >>> >>> We had a 60Gb chunk and someone was loading lots of data into it. >>> >>> 5 minute checkpoint interval and checkpoints up to 6 minutes long! >>> >>> Just what I needed when running a program that inserts into temp >>> tables. >>> >>> My program went from 2 minutes to 20 minutes! >> >> Good point David. The solution would be to use fractional values for >> LRU_MIN/MAX_DIRTY to make sure that there are very few dirty pages at >> checkpoint time. Not a complete solution, but it will help with 'larger' >> chunks if not 'huge' ones. > > >Are you both saying that an inevitable consequence of large chunks is long >checkpoint times at times of high update? > >I guess this isn't just an IDS 10 thing ...? > Another reason to take advantage of the fractional values of the LRU_MIN/MAX_DIRTY variables. JWC