Tracing for Parallelism

 

alter session set tracefile_identifier='PX_serial';
alter session set events 'trace[PX_Messaging]disk high';
alter session set events 'trace[SQL_Parallel_Compilation | SQL_Parallel_Optimization]disk high';
alter session set events 'trace [Parallel_Execution.*] disk high';
alter session set events '10053 trace name context forever, level 1';
alter session set events 'trace[SQL_Code_Generator] disk high';
alter session set events 'trace[SQL_Compiler]disk high';
.
< Execute the problematic SELECT stmt >
.
alter session set events 'trace[SQL_Parallel_Compilation | SQL_Parallel_Optimization] off';
alter session set events 'trace [Parallel_Execution.*] off';
alter session set events '10053 trace name context off';
alter session set events 'trace[SQL_Code_Generator] off';
alter session set events 'trace[SQL_Compiler] off';
alter session set events 'trace[PX_Messaging] off';




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