Re: Adding SQL indes causing performance degradation?

Folks,

Another thing to check - especially if the PF is large - is to see what the 
setting is for SMAPP.  The easiest way is to EDTRCYAP and see what the time 
setting is.  SMAPP will automatically journal an index for you if it decides it 
needs to - which can have a SIGNIFICANT impact on your performance.

Michael

> 
> This may be a long shot, but I have seen references to performance 
> degradation when you have access paths that have different values for the 
> ACCPTHSIZ parm.  As an example. maybe your existing DDS files all have a 
> value of *MAX4GB and the new SQL Indexes have a value of *MAX1TB.
> 
> If that is the case, do CHGPF/CHGLF to make them all the same and I 
> believe it will make a difference.
> 
> Mark

> 
> 
> "Chevalier, Rick" <Rick.Chevalier@xxxxxxxxxxxxxxx>
> Sent by: midrange-l-bounces@xxxxxxxxxxxx
> 04/08/2003 01:02 PM
> Please respond to Midrange Systems Technical Discussion
> 
>        To:     "'Midrange Systems Technical Discussion'" 
> <midrange-l@xxxxxxxxxxxx>
>        cc: 
>        Subject:        RE: Adding SQL indes causing performance 
> degradation?
> 
> 
> Bruce wrote:
> it's a well known fact that adding indexes has a performance impact for
> update jobs. Seizes over the index plus checking to see if the index needs
> updating and then performing the update to the index are added to the job
> the performs the update.
> 
> Bruce,
> I agree that there will be a performance impact created by adding even a
> single index.  We are seeing a job that averaged a run time of 60 minutes
> now averaging between 80 and 90 minutes.  This is an increase of at least 
> a
> third.  That sounds like a lot of overhead just to maintain 
> new indexes.
> 
> Rick