Parse times in Oracle 11G

Question

Has anyone else experienced extremely long parse times for Oracle 11G versus 10G? We are experiencing at least a 10 times increase in the parsing of our SQL statements. This is causing our customers to complain when running reports which contain several SQL statements that aren't in the SGA due to the infrequent use. I have opened a Service Request and development stated that this is to be expected with Oracle 11G due to the new optimizer features. I have tried to disable the features by settting the optimizer version to anything but 11G and no setting has helped. To make thing even worse, this increased parse time is on a new server that should be 2.5 times faster than the server that is running the 10G database. I do get at least a 2.5 times increase, larger if I/O intensive, in almost every other aspect of the database except for the parse times.

Answer 1

user5999814 wrote:
I wondered what the resolution was to this issue. We currently experiencing this will our Oracle 11.1.0.7 database with a small but important set of queries and it seems to be getting worse. We first noticed it with a query that went from taking 3.5 seconds to 7 seconds. A SQLTrace / TKProf revealed that 99% of the time was being spent during the parsing. A second similar query that brings in more data is taking around 1.5 minutes to parse then only a few seconds to actually execute. These are queries that are part of on online web transaction so this is not acceptable. We are able to replicate the behavior in multiple database instances.As a starting point it would be interesting to see the tkprof output from :
alter session set events '10046 trace name context forever, level 8';
+your select statement+
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Regards
Jonathan Lewis
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