Re: pgbench tps drop from 5000 to 37 going from localhost to a server 13ms away

On 24/07/2015 22:51, Jeff Janes wrote:
> starting vacuum...end.
>
> transaction type: TPC-B (sort of)
> scaling factor: 1
>
>
> This is your problem. There is only one row in the pgbench_branch
> table, and every transaction has to update that one row. This is
> inherently a seriaized event.
Indeed it was!
> One solution is to just use a large scale on the benchmark so that
> they upate random pgbench_branch rows, rather than all updating the
> same row:
>
> pgbench -i -s50
With a scale of 1000, everything except the END took roughly the latency
time. Interestingly, the END still seems to take more, when
threads/clients are really ramped up (100 vs 8). Why would that be?
> Alternatively, you could write a custom file so that all 7 commands
> are sent down in one packet.
How would you restructure the sql so as the make that happen?

cheers,

Chris