Question : Sybase 12.5 Performancing and Tuning

Hi,

Performance and Tuning is a very fundamental aspect of databases.

Could an expert possibly provide some pointers on what one should do
if a production stored procedure is performing badly?  

Say the scenario is : a production overnight batch job ran and took a very long time.  It was not taking more than 60% of the time on  DEV or UAT servers. NB NO other process was running at the time (to rule out blocking contention etc).

Are there new features available in Version 12/12.5 that allow us to run
utilities on the prod box (other than sp_showplan).  We don't really
want to be running queries on the prod box unless we can't reproduce
the problem in the DEV environment.

Basically, what I'm after is pointers on how to go about finding out why the sproc was
running slowly.

Thanks!

Regards,

nuz1.

Answer : Sybase 12.5 Performancing and Tuning

While there are some new SET options introduced in most new versions, I can't think of any diagnostic one that wasn't already around from ages ago.

The ones I already mention :

SET SHOWPLAN ON
SET STATISTICS IO ON

have been around pretty much forever.

The stored procedure sp_showplan (lets you check the showplan of a process while it's actually running, as opposed to SET SHOWPLAN ON which requires you to actually run the commans yourself from your current session) was introduced in 11.5, but that's been around since ... 1998, I think.

It's possible whoever told you this is thinking of the "MDA" tables, introduced in 12.5.0.3, which do offer another window into sql text and query plans, but they're fairly specialised and from the things we were discussing, it isn't time yet to be getting into them.

Another possibility is dbcc sqltext, which I think is ASE 12.0 but it might be 12.5, but that only reports on the actual SQL text and doesn't provide any diagnostics.

So, no, I think SHOWPLAN, STATISTICS IO and sp_sysmon are still the first and best tools to be using in any performance investigation...

Good luck!