IBM Mainframe Forum Index
 
Log In
 
IBM Mainframe Forum Index Mainframe: Search IBM Mainframe Forum: FAQ Register
 

PROCSU reduction impact measure


IBM Mainframe Forums -> DB2
Post new topic   Reply to topic
View previous topic :: View next topic  
Author Message
rajas

New User


Joined: 02 Sep 2010
Posts: 1
Location: Pune

PostPosted: Thu Sep 02, 2010 7:54 pm
Reply with quote

Hi,

Am facing a strange situation. We were trying to improve performance for some query. On doing some query modifications; PROCSU in DSN_STATMNT_TABLE did reduce from 4 to 1. But when I run the jobs using these queries with the same volume of input file records; CPU time is almost same. Does the change in PROCSU reflects somewhere else and not CPU time? Then how the performance would impact. Please share your thoughts.
Back to top
View user's profile Send private message
VENKATA S KRISHNAMOORTHY

New User


Joined: 03 Sep 2010
Posts: 3
Location: CHENNAI, INDIA

PostPosted: Fri Sep 03, 2010 10:57 pm
Reply with quote

DB2 EXPLAIN is dynamic in nature. PROCSU is more like a hint provided by optimizer on how much service units (read as resource) a query "might" consume. When you bind your package and execute the actual query optimizer may take a more informed decision depending upon various factors. It is always better to use EXPLAIN PROCSU as an estimate.
Back to top
View user's profile Send private message
View previous topic :: :: View next topic  
Post new topic   Reply to topic View Bookmarks
All times are GMT + 6 Hours
Forum Index -> DB2

 


Similar Topics
Topic Forum Replies
No new posts MIPS/CPU consumption reduction in Batch DFSORT/ICETOOL 4
This topic is locked: you cannot edit posts or make replies. MIPS reduction for Batch job All Other Mainframe Topics 8
No new posts z/OS V2R2 Migration Impact on Existin... All Other Mainframe Topics 4
No new posts Increasing a record length of vsam fi... JCL & VSAM 5
No new posts BMC unload execution time reduction IMS DB/DC 14
Search our Forums:

Back to Top