>> I am thinking about to implement "multi-master" option for pgbench.
>> Supose we have multiple PostgreSQL running on host1 and host2.
>> Something like "pgbench -c 10 -h host1,host2..." will create 5
>> connections to host1 and host2 and send queries to host1 and host2.
>> The point of this functionality is to test some cluster software which
>> have a capability to create multi-master configuration.
>>
> Perhaps the read option has a good interest for PostgreSQL to check a
> simultaneous load on a multiple cluster of Postgres with read operations.
> But I do not see any immediate use of write operations only. Have you
> thought about the possibility to define a different set of transaction
> depending on the node targetted? For example you could target a master with
> write-read and slaves with read-only.
I think that kind of "intelligence" is beyond scope of pgbench. I
would prefer to leave such a work to another tool.
> Btw, this could have some use not only for Postgres, but also for other
> projects based on it with which you could really do some multi-master
> benchmark in writing.
Right. If pgbench could have such a functionarlity, we could compare
those projects by using pgbench. Currently those projects use
different benchmarking tools. That means, the comparison is something
like apple-to-orange. With enhanced pgbench we could do apple-to-apple
comparison.
> Do you have some thoughts about the possible option specifications?
> Configuration files would be too heavy for the only purpose of pgbench. So,
> specifiying all the info in a single command? It is of course possible, but
> command will become easily unreadable, and it might be the cause of many
> mistakes.
Agreed.
> However, here are some ideas you might use:
> 1) pgbench -h host1:port1,host2:port2 ...
> 2) pgbench -h host1,host2 -p port1:port2
Looks good.
--
Tatsuo Ishii
SRA OSS, Inc. Japan
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