Re: Add min and max execute statement time in pg_stat_statement

On Wed, Jan 22, 2014 at 3:32 AM, KONDO Mitsumasa
<kondo.mitsumasa@lab.ntt.co.jp> wrote:
>> OK, Kondo, please demonstrate benchmarks that show we have <1% impact
>> from this change. Otherwise we may need a config parameter to allow
>> the calculation.
>
> OK, testing DBT-2 now. However, error range of benchmark might be 1% higher.
> So I show you detail HTML results.

To see any impact from spinlock contention, I think you're pretty much
going to need a machine with >32 cores, I think, and lots of
concurrency.  pgbench -S is probably a better test than DBT-2, because
it leaves out all the writing, so percentage-wise more time will be
spent doing things like updating the pgss hash table.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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