Re: Update Statistics Speedup Help???

Believe it or not, I'd have to set the environment variable in informix.rc, bounce SAP, do the reorgs and reset and rebounce the system (SAPDBA doesn't allow you to set it on the fly...). I am going to try it though, and report it for other Informix SAPers to take advantage of.... What's the deal with temp DBspaces?? Any guidelines for how to size them for maximum performance and parallelism??? Generally I know you want them spacious and numerous, but better ROT's would be welcome. What are the penalties for undersizing them or oversizing them?? Maybe we should start an SAP annex to the FAQ??? It's a very different critter to handle - out of the box the system typically installs > 10,000 tables controlled via its data dictionary and Open SQL preprocessing, which ends up in the form of >8000 tables that the DBMS sees. Yes - that means some tables are pooled into single DBMS tables - goes back to the days when RDBMS'S couldn't handle so many tables.... I might be able to name 30ish of them on a good day. It comes with tools for managing the database that also work with the data dictionary, so this is why I don't screw around with the database behind SAP's back unless I have to. This is why I don't do UPDATE STATS in parallel, or fragment a lot (can be done but it's clunky, and typically only done to the 5 or 10 or 20 largest tables), and why I can't monkey with the code. Indeed I was kind of trolling for Art, I suspect he's got it pretty well doped out.... Thanks - keep those suggestions coming... Greg David Williams wrote: > snip.... > > Run it wiht a higher PDQPRIORITY. Allocate many temp dbspaces spread > across disks (1 temp dbspace per disk). Be aware that there have been > problems with unevenly sized temp dbspaces and when one fills up > Online does not use the next one but gives an error to your session. > I would size all your temp dbspaces evenly and not make them too > small. > > Fragmenting tables more may help, allowing more scan threads to be > generated hence increases parallelism (Art - bet you have some useful > experince here, one for the FAQ please??). > > -- > David Williams snip......