Re: pgbench duration option

On Mon, 18 Aug 2008, Tom Lane wrote:

> the seldom-used log-each-transaction option, which pretty obviously
>  is a drag on performance anyway

I always recommend that people run with log each transaction turned on, 
beause it's the only way to gather useful latency information.  I think 
runs that measure TPS without even considering that are much less useful. 
The fact that it's seldom used is something I consider a problem with 
pgbench.

> I repeat my concern that transaction rates measured with this patch will
> be significantly different from those seen with the old code

Last time I tried to quantify the overhead of logging with timestamps on I 
couldn't even measure its impact, it was lower than the usual pgbench 
noise.  That was on Linux.  Do you have a suggestion for a platform that 
it's a problem on that I might be able to use?  I'd like to do some 
measurements.

--
* Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD