Bruce Momjian escribió:
> On Fri, May 3, 2013 at 05:24:54PM +0200, Andres Freund wrote:
> > The problem with an extra metadata fork is that it essentially would
> > double the files in a cluster and it would also noticeably increase the
> > amount of open files we need.
> > There have been quite some complaints about CREATE DATABASE speed, I
> > am not sure we want to make it even slower :(
>
> Agreed. We start to get into file system performance issues at that
> point. I have often wondered if we need to create hash the files into
> subdirectories for databases with many tables. Has anyone profiled
> this?
Modern filesystems use trees to store file nowadays, not linear arrays,
and so that old scenario (long time to find one specific directory entry
within a directory containing lots of files) is no longer that serious a
problem.
--
Álvaro Herrera http://www.2ndQuadrant.com/
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