Greg Smith <greg <at> 2ndquadrant.com> writes: > Could you try this again with "top -c", which will label these > postmaster processes usefully, and include the pgbench client itself in > what you post? It's hard to sort out what's going on in these > situations without that style of breakdown.
As a further experiment, I ran 8 pgbench processes in parallel. The result is about the same.
Let's start from the beginning. Have you tuned your postgresql.conf file? What do you have shared_buffers set to? That would have the biggest effect on a test like this.