Re: Postgresql in a Virtual Machine

On 11/25/2013 12:01 PM, Lee Nguyen wrote:
> Hi,
>
> Having attended a few PGCons, I've always heard the remark from a few
> presenters and attendees that Postgres shouldn't be run inside a VM. That
> bare metal is the only way to go.

This is pretty dated advice.  Early VMs had horrible performance under
load, which is mostly where this thinking comes from.  It's not true
anymore.

It *is* true that getting good performance in a virtualized environment
requires more tuning than bare metal, because you have to tune the VM
system as well.

> Here at work we were entertaining the idea of running our Postgres database
> on our VM farm alongside our application vm's.  We are planning to run a
> few Postgres synchronous replication nodes.

Biggest pitfall here is IO performance configuration.  I can't give you
specific advice without knowing the platform and the desired workload.

--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com