Re: postgres 9.3 vs. 9.4 - Mailing list pgsql-performance

On Thu, Sep 18, 2014 at 4:58 AM, Mkrtchyan, Tigran
<tigran.mkrtchyan@desy.de> wrote:
>
> 9.3.5:
>         0.035940        END;
>
>
> 9.4beta2:
>         0.957854        END;


time being spent on 'END' is definitely suggesting i/o related issues.
This is making me very skeptical that postgres is the source of the
problem.   I also thing synchronous_commit is not set properly on the
new instance (or possibly there is a bug or some such).  Can you
verify via:

select * from pg_settings where name = 'synchronous_commit';

on both servers?

What is iowait?  For pci-e SSD, these drives don't seem very fast...

merlin