Skip to Main Content

Tuning (SQL Query has radically different Buffer GETS in each instance)

540395May 11 2007 — edited May 24 2007

I have been noticing that on Node2 of my 10.2.0.3 RAC cluster CPU has been running 90% for the past couple of days and on Node1 we are at the normal 20-30%. I was comparing AWR for both instances and noticed that the same exact SQL was showing different GETS on each instance.

Both Instances are configured exactly the same. SGA 3GB, 2 dual core 1.5Ghz CPU on Solaris 10.

AWR For Node 1

SQL ordered by Gets
Resources reported for PL/SQL code includes the resources used by all SQL statements called by the code. 
Total Buffer Gets: 8,199,224 
Captured SQL account for 94.2% of Total 
Buffer Gets  Executions  Gets per Exec  %Total CPU Time (s) Elapsed Time (s) SQL Id SQL Module SQL Text 
4,834,470 16,465 293.62 58.96 442.34 459.42 cs3w0nz7uanhc    BEGIN HRW_EC_QUERY.CHECK_STUDE... 
4,561,082 16,469 276.95 55.63 411.10 430.16 6vbpbvfburc4x    SELECT COUNT(SECURE_PROGRAMS.P... 

AWR For Node 2

Buffer Gets  Executions  Gets per Exec  %Total CPU Time (s) Elapsed Time (s) SQL Id SQL Module SQL Text 
219,779,881 9,306 23,617.01 99.26 11791.62 32202.99 cs3w0nz7uanhc    BEGIN HRW_EC_QUERY.CHECK_STUDE... 
219,320,634 9,302 23,577.79 99.05 11760.22 32137.23 6vbpbvfburc4x    SELECT COUNT(SECURE_PROGRAMS.P... 

Gets on Node 2 are about 45 times what they are on node 1. We are using bind variables in the SQL. The statements are completely identical. Anyone seen this before?

Thanks,
Brian

Comments
Post Details
Added on May 11 2007
10 comments
1,869 views