Re: Duplicate Databases

%UNIPLEX %TO informix-list@rmy.emory.edu %FROM rridley %SYSTEM DHLNET %SUBJECT Re: Duplicate Databases %VERIFY y %DATE 31/03/93 10:56 %REFERENCE 17204 Joe Hartley writes: >We've got a Sun 4/470 running SunOS 4.1.3 and an >accounting/manufacturing/ order admin application that uses >Informix/SE as its underlying RDBMS. The app requires SE; On-line >is out of the question. Excuse the question, but why would an application 'require' SE ? ...Just interested to know :).... This sounds like one of those times where On-line performance would greatly out-strip SE, as the transaction rate would be fairly large. >The problem: At the end of the month, the orders are coming in fast >and furious and the OA and production staffs are working full steam >trying to get the orders out. Unfortunately, at the same time, the >beancounters and salespeople run all sorts of CPU and I/O intensive >reports trying to figure out where the sales are in relationship to >the forecasts. This has the effect of bringing the app to its knees, >making it more difficult for the OA and Prod folks to get the real >work done. >What we'd like to do is find some way of mirroring the main database >in a timely fashion so that the reports can be run off of the DB >copy, keeping the record locking to a minimum on the working >database. In the previous paragraph you state that the reports are CPU and I/O intensive, whereas now it appears to be record locking - is it necessary for the reports to be locking data ? Could you not use 'dirty reads'? >I don't think that RAIDs are the answer here, just some sort of >brilliant software solution. Has anyone faced and conquered this >problem before? I would say that you would have to balance 'accuracy of data in reports' against 'performance of machine' - if you had another machine that you could put a 'snapshot' copy of the database on, and use that to run reports on, then that would probably help, but that's not exactly 'real-time reporting', is it :) ? Have you tried monitoring exactly which resources are the bottleneck and perhaps trying to balance loads or remove 'hogs' to ease the bottleneck ? If disk I/O is the problem (or one of them), for example, perhaps you could add another disk to share the load but whether this would help would depend on your current set-up. IMHO RAIDS would definitely not be the answer - they would probably slow you down if anything. Good Luck! Cheers, Richard Ridley %UEND