Re: pgbench stats per script & other stuff - Mailing list pgsql-hackers

From Fabien COELHO
Subject Re: pgbench stats per script & other stuff
Date
Msg-id alpine.DEB.2.10.1603200725210.7678@sto
Whole thread Raw
In response to Re: pgbench stats per script & other stuff  (Jeff Janes <jeff.janes@gmail.com>)
Responses Re: pgbench stats per script & other stuff
List pgsql-hackers
Hello Jeff,

> So I wanted to do something like:
>
> for f in `seq 0 5 100`; do
>  pgbench -T 180 -c8 -j8 -b tpcb-like@$f -b select-only@100
> done;
>
> But, I'm not allowed to specify a weight of zero.

Indeed. I did not envision such a use case, but it is quite legitimate and 
interesting! I would hope that the behavior would be a linear combination 
of the raw performance of each script, but whether it is indeed the case 
is not that sure.

> Would this be a welcome change?

Speaking for myself, I would be fine with such a change, provided:
 - that it does work:-) I'm not sure what happens by the script selection   process, it should be checked carefully
becauseit was not designed   with allowing a zero weight, and it may depend on its/their positions.   It may already
work,but it really needs checking.
 
 - I would suggest that a warning is shown when a weight is zero,   something like "warning, script #%d weight is zero,
willbe ignored".
 
 - the documentation should be updated:-)

-- 
Fabien



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