Re: postgres block size alignment with filesystem block size

On Wed, Jun 06, 2012 at 12:24:35PM -0400, Tom Lane wrote:
> Mike Broers <mbroers@gmail.com> writes:
> > Hello, I am setting up a new postgres production server in a managed
> > hosting environment.  I dont have much insight into the underlying disk
> > architecture but the filesystem I have been presented with has a 4k block
> > size.  Postgres defaults to 8k block size; would it be beneficial to repave
> > the filesystem at an 8k block size or problematic to leave it at 4k?
>
> I doubt it's worth the trouble to change it.  Most filesystems default
> to 4k or smaller block sizes, so that's what PG is accustomed to run on.
> I think it would only really be an issue if PG's block size weren't a
> multiple of the filesystem block.

I have heard about performance issues when the virtual machine block
size isn't aligned with the host OS block size.

--
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + It's impossible for everything to be true. +