[Linux-cluster] Starter Cluster / GFS

[Marti, Robert]

> -----Original Message-----
> From: linux-cluster-bounces at redhat.com [mailto:linux-cluster-
> bounces at redhat.com] On Behalf Of Nicolas Ross
> Sent: Wednesday, November 10, 2010 1:32 PM
> To: linux clustering
> Subject: Re: [Linux-cluster] Starter Cluster / GFS
> 
> > We had to make similar changes to our application.
> >
> > Avoid allowing two (or more) hosts to create small files in the same
> > shared directory within a GFS filesystem.  That particular case scales
> > poorly with GFS.
> >
> > If you can partition things so that two hosts will never create files
> > in the same directory (we used a per-host directory structure for our
> > application), or perhaps direct all write operations to one host while
> > other hosts only read from GFS, it should perform well.
> 
> Ok, I see. Our applications will read/write into its own directory most of the
> time. In the rare cases when it'll be possible that 2 nodes read/writes to the
> same directory, it'll be for php sessions files. If we ever need to reach to this
> stage, we'll have to make a custom session handler to put them into a central
> memcached or something else...
> 

If that's the case, why look at shared storage at all?