Re: [Sequoia] PostgreSQL Documentation of High Availability

Markus Schiltknecht wrote:
> Hello Emmanuel,
>
> Emmanuel Cecchet wrote:
> >>> Even here I think that there is a common misconception between
> >>> performance and scalability. Most people think that by having
> >>> multiple nodes their query will run faster which is obviously wrong
> >>> if your original workload does not saturate a single node.
> >>
> >> Sure. Do you think that should be made clearer?
> > Yes, I think so because this is a very common belief that we experience
> > with new users.
>
> Okay, I have forwarded that to Bruce, who's editing the documentation
> (and is a native English speaker). I'm not sure how we can cover this,
> as we are very general in our description.

OK, updated:

<term>Multi-Server Parallel Query Execution</term>
<listitem>

<para>
Many of the above solutions allow multiple servers to handle
multiple queries, but none allow a single query to use multiple
servers to complete faster. This solution allows multiple
servers to work concurrently on a single query. This is usually
accomplished by splitting the data among servers and having
each server execute its part of the query and return results
to a central server where they are combined and returned to
the user. Pgpool-II has this capability.

--
Bruce Momjian bruce(at)momjian(dot)us
EnterpriseDB http://www.enterprisedb.com

+ If your life is a hard drive, Christ can be your backup. +