Re: Engine Performance Requirements - Help !

In article <813590003.5111@compsys.demon.co.uk> "tech@compsys.demon.co.uk" <158.152.33.120> writes: >Hi All, > >We are currently developing an Informix 4GL application for one of >our customers. We currently run SCO UNIX 3.2.4, Informix SE/4GL/RDS/ID >on a 486 server. > >Although the database has been developed under SE the customer has now >specified required data retrieval times and record estimates that >we feel are out of SE capabilities. These values are far greater than >when the project was started... > >The customer wants data retrieval time of < 1 sec from queries >were data is entered into key indexed fields. >eg.select * from <tab_name> where <key_field1> = <value> > Should be achievable. I was getting this access time for an indexed hit using Informix 2.1 on a Compaq 386/20 running ISC unix in 1989. Database table had over 150,000 records. >We are in the process of running tests on SE with files approx 20MB >in size. > This is tiny. >Should we be looking at OnLine and forgetting SE altogether ? > IMO, no but I don't use OnLine, haven't needed it yet. >Also, has anyone had experience running this size of database on a >486/Pentium server (such as a Compaq ProLiant) ? > I'm currently running a bigger database on a clone 486/66, Informix 5.01 SE and Solaris 2.4 X86 unix. >Does anyone have any idea of the minimum Informix/Server spec. >that we should be looking at ? > To give you an idea, one of my systems hit 600MB a year ago. It was running on a SPARC 2 with 32Mb RAM using SE engine. Indexed searches on the main table with 760,000 rows ranged from damn near instantaneous for a unique key to 30 seconds for a PREPARE, OPEN & FETCH on a really poor, non-unique (but necessary) index. This one was fetching all patient records selecting on mother's given name, sex of child and a date of birth range. We upgraded to a SPARC 5 with 64 Mb because we had the money. Users claim no great performance improvement, so it's not RAM or CPU bound (which is what I expected and why I added a spindle. Just need time to move some of the files...) This database is now pushing 800MB and running fine. User load is max 8, though, so lots of users might change things. >Any suggestions and help would be greatly appreciated Do some testing. Run up a table with 100,000 rows and test response time to queries. Think about splitting the table if practical to get more rows/page. There were some good tips in one of the Informix manuals, but I can't remember which one :(. But in my experience, SE on a unix platform is easily capable of the performance you're needing. Peter Wiley