Posts Tagged ‘Performance’
Index Access best approach?? Not Always…
There is a common misconception that Index access is the best access method for query execution. This approach leads to people concentrate on removing Full Table Scans (FTS) from the Query execution plan. I recently worked on a performance tuning issue where I found such [Read More]
Resolving Shutdown Immediate Hang Situations
Many times Oracle DBA’s are faced with a situation where shutting down the instance with shutdown immediate seems to take infinite time and gives a impression that the session is hung. In most of the cases this is not a hang. Hang can be defined as a scenario when few [Read More]
Tracing Sessions with Event 10046
10046 Event is used to trace SQL statements (similar to sql_trace=true) with additional details depending on the tracing level which is specified. 10046 EVENT levels: 1 – Enable standard SQL_TRACE functionality (Default) 4 – As Level 1 PLUS trace bind values 8 [Read More]
Sign on Letter to Larry Ellison on AWR and ASH Licensing
While surfing across the blog’s, I found this particular link, a compaign which is aimed at getting free access to the ASH and AWR reports. I believe most of us know that we need to pay extra fees for the Diagnostic Tuning Pack which also includes ASH and AWR report. [Read More]
HW enqueue contention with LOB
DefinitionEnqueues are local locks that serialize access to various resources. Enqueue wait event indicates a wait for a lock that is held by another session (or sessions) in an incompatible mode to the requested mode. HW Enqueue – High Watermark enqueue is acquired [Read More]
Diagnostics For Database Hang
Many times Oracle DBA’s are in a situation when the database is hung and does not seem to be responding. In some scenarios, state is such that you cannot even connect to the sqlplus session. Majority people restart the database (Sometimes I wonder if this is due to [Read More]
