Re: How much expensive are row level statistics? - Mailing list pgsql-performance

From Bruce Momjian
Subject Re: How much expensive are row level statistics?
Date
Msg-id 200512170244.jBH2iJV11094@candle.pha.pa.us
Whole thread Raw
In response to Re: How much expensive are row level statistics?  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-performance
Tom Lane wrote:
> Michael Fuhr <mike@fuhr.org> writes:
> > Further tests show that for this application
> > the killer is stats_command_string, not stats_block_level or
> > stats_row_level.
>
> I tried it with pgbench -c 10, and got these results:
>     41% reduction in TPS rate for stats_command_string

Woh, 41%.  That's just off the charts!  What are we doing internally
that would cause that?

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