Re: High context switches occurring - Mailing list pgsql-performance

From Bruce Momjian
Subject Re: High context switches occurring
Date
Msg-id 200512070434.jB74Y4o20004@candle.pha.pa.us
Whole thread Raw
In response to Re: High context switches occurring  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: High context switches occurring
List pgsql-performance
Tom Lane wrote:
> "Anjan Dave" <adave@vantage.com> writes:
> > -bash-3.00$ time pgbench -c 1000 -t 30 pgbench
> > starting vacuum...end.
> > transaction type: TPC-B (sort of)
> > scaling factor: 1
> > number of clients: 1000
> > number of transactions per client: 30
> > number of transactions actually processed: 30000/30000
> > tps = 45.871234 (including connections establishing)
> > tps = 46.092629 (excluding connections establishing)
>
> I can hardly think of a worse way to run pgbench :-(.  These numbers are
> about meaningless, for two reasons:
>
> 1. You don't want number of clients (-c) much higher than scaling factor
> (-s in the initialization step).  The number of rows in the "branches"
> table will equal -s, and since every transaction updates one

Should we throw a warning when someone runs the test this way?

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