Re: On-Line 7 Performance

In article <3319777C.564D@netcomuk.co.uk>, Neil Truby <ntruby@netcomuk.co.uk> writes >Rudy Fernandes wrote: >> >> In article <331606A3.1EAB@iap.net.au>, >> Andrew Mercer <amercer@iap.net.au> wrote: >> >We too are having performance problems similar to other postings in this >> >newsgroup. I suppose it is the nature of newsgroups that only problems >> >are posted, but are there any sites that are happy with On-Line DSA. >> >> Yes, here's one! >> >> We have recently migrated from SE 5.0 to ONLINE 7.20 with no change to >> our hardware. >> >> After some initial hiccups, performance under ONLINE is equal to or better >> than under SE (Index builds under ONLINE are phenomenally fast). >> >> During the initial period, performance of ONLINE was as low as 30-35% of >> SE. I've concluded that the following parameters were significant. >> >> BUFFERS keep at about 25% of Physical memory >> RESIDENT 0>> DBSPACETEMP pointed to 2 temporary dbspaces >> MAX_PDQPRIORITY 0 >> OPTCOMPIND 0>> PHYSDBS separate disk. [Logical logs, Data and Physical log are each >> on separate disks (Data spread on 2 disks)] >> >> In case checkpoints are too long (during which the system may appear to hang), >> you may want to look at the following 2 parameters >> >> LRU_MAX_DIRTY >> LRU_MIN_DIRTY>> >> At our site, we have brought them down from the default 60 and 50 to 2 and 1. >> HTH >> >> ---------------------- >> Rudy Fernandes >> GIC, Kuwait >> ---------------------- > >I would broadly endorse your settings, although I have my logs, phys and >logical, in one dbspace. > >I'm interested in your having RESIDENT set to 0. Informix Tech Support >recommended to me that it should be set to 1 if it has no significant >effect on the paging rate. > >What are your, and others' experiences? > >Neil Truby >Chase Manhattan Bank >Bournemouth, UK I normally set it to 1 as advised by Informix and I have yet to have any performance problems...I notice the defaults in OWS 7.20.UC1 is 0. -- David Williams