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I am looking for a performance tuning doucment(DB2 UDB v7.2 fixpak 5 and aix 5.2),changes need to be done to the database for increasing the performance. can you please provide any link/document for this.
You may want to apply the latest FixPak because pretty much each FP includes improvements in the DB2 Optimizer (but probably nothing that you will really notice).
__________________
Knut Stolze
IBM DB2 Analytics Accelerator
IBM Germany Research & Development
You may want to apply the latest FixPak because pretty much each FP includes improvements in the DB2 Optimizer (but probably nothing that you will really notice).
I still suggest to try fixpacks behaviour on test system. Optimizer is complex mechanism and can lead to poorer performance also. For example few years ago when I have migrated database from v7 to v8 there was some performance degradation on some particular SQLs on my data warehouse system. SQLs that usually executed in 2 minutes was according to my calculation running 40 days (I haven't waited 40 days to see the result, I just saw frequency of insert statements). Reporting PMR to IBM and IBM lab made a special build that solved the problem. So before applying any fixpacks I always performance of critical SQL statements - this are usually the complex SQLs.
I am looking for a performance tuning doucment(DB2 UDB v7.2 fixpak 5 and aix 5.2),changes need to be done to the database for increasing the performance. can you please provide any link/document for this.
Any Help...
Thanks in Advance
Meena.s
Hi,
According to my experience there are almost always SQL problems on database and not environment itself. I guess your system is up an running for some years, so there was probably some kind of tuning on database already done on db site. So I suggest turning on SQL-snapshot or SQL-monitoring to see which SQLs are making a performance problem. Then execute explain and try to create some indexes on database.
Hope this helps,
Grofaty
I still suggest to try fixpacks behaviour on test system. Optimizer is complex mechanism and can lead to poorer performance also. For example few years ago when I have migrated database from v7 to v8 there was some performance degradation on some particular SQLs on my data warehouse system. SQLs that usually executed in 2 minutes was according to my calculation running 40 days (I haven't waited 40 days to see the result, I just saw frequency of insert statements). Reporting PMR to IBM and IBM lab made a special build that solved the problem. So before applying any fixpacks I always performance of critical SQL statements - this are usually the complex SQLs.
Very good advise. (Even if this should be common sense.)
__________________
Knut Stolze
IBM DB2 Analytics Accelerator
IBM Germany Research & Development