Re: Initiating Checkpoints manually

I have LRU_MAX_DIRTY 3 LRU_MIN_DIRTY 1 BUFFERS 300,000 (system page size 2k) LRUS 64 Thanks Vinod Bhansali Informix DBA DSL Transportation >From: "Rudolf Fernandes" <rferdy@nortelnetworks.com> >To: Vinod Bhansali <iiug@hotmail.com> >Subject: Re: Initiating Checkpoints manually >Date: Thu, 01 Jun 2000 15:34:14 -0400 > >Vinod Bhansali wrote: > > > Hello friends, > > > > I want to tune the checkpoint duration by trying different values for >the > > ckptintvl. > >CKPTINTVL is not normally used to tune one's checkpoint duration, although >in >theory, like the physical log size, it can be used. Rather, in the tuning >perspective, it provides a means of balancing disk writes against duration >of >Fast Recovery. > >One's checkpoint duration, keeping OS/Hardware/Db space layout variables >constant, is primarily dependant on the number of dirty buffers at >checkpoint >time - those have to be flushed to disk and it is this process which takes >time. The number of dirty buffers, in turn, is primarily dependant on 3 >onconfig parameters - LRU_MAX_DIRTY, LRU_MIN_DIRTY and BUFFERS. > >You should be fiddling with LRU_MAX_DIRTY & LRU_MIN_DIRTY to tune your >checkpoint duration. Unfortunately, that does require you to bounce your >engine. > >Rudy > > > > But as we need to initialise shared memory after each change I am > > planning to initiate checkpoints manually by writing some shell as below > > > > onmode -c> > sleep 50 > > > > What do you say? Is it ok? Has anyone faced any problems in this? > > > > Thanks in advance > > Vinod Bhansali > > Informix DBA > > DSL Transportation > > ________________________________________________________________________ > > Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com > ________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com