Re: Reduce timing overhead of EXPLAIN ANALYZE using rdtsc? - Mailing list pgsql-hackers

From Tomas Vondra
Subject Re: Reduce timing overhead of EXPLAIN ANALYZE using rdtsc?
Date
Msg-id c0c253a0-4825-f295-1583-50f9bbab7d5f@enterprisedb.com
Whole thread Raw
In response to Re: Reduce timing overhead of EXPLAIN ANALYZE using rdtsc?  (David Geier <geidav.pg@gmail.com>)
Responses Re: Reduce timing overhead of EXPLAIN ANALYZE using rdtsc?
List pgsql-hackers
Hi,

there's minor bitrot in the Mkvcbuild.pm change, making cfbot unhappy.

As for the patch, I don't have much comments. I'm wondering if it'd be
useful to indicate which timing source was actually used for EXPLAIN
ANALYZE, say something like:

 Planning time: 0.197 ms
 Execution time: 0.225 ms
 Timing source: clock_gettime (or tsc)

There has been a proposal to expose this as a GUC (or perhaps as explain
option), to allow users to pick what timing source to use. I wouldn't go
that far - AFAICS is this is meant to be universally better when
available. But knowing which source was used seems useful.


regards

-- 
Tomas Vondra
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



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