On Fri, Aug 20, 2010 at 8:45 AM, Greg Stark <gsstark@mit.edu> wrote:
> On Fri, Aug 20, 2010 at 3:43 AM, Robert Haas <robertmhaas@gmail.com> wrote:
>> A related, interesting question is whether there's any purpose to the
>> smgr layer at all. Would we accept a patch that implemented an
>> alternative smgr layer, perhaps on a per-tablespace basis?
>
> I definitely want to keep it.
>
> I think we could usefully do an application-level raid implementation.
> It would be useful for people running on machines where they don't
> have administrative access on the machine. In particular I'm picturing
> shared cluster machines that run other jobs and can't be reconfigured
> specifically for the database. Adding per-tablespace behaviour would
> make the argument a lot stronger too since it's not so easy to set up
> different stripe sizes per table if you're using OS level raid.
That would actually be kind of cool.
> I also have various crazy plans to experiment with network-based
> storage and had intended to use smgr to do so. At google we have a
> bunch of different storage technologies and they're all
> application-level network services. You can always implement a fuse
> module that calls back up to a daemon which acts as the client but
> that doesn't make me feel any happier about it.
Me either.
I really like the idea of trying to use network-based storage in some
way. Gigabit Ethernet is a big I/O channel.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise Postgres Company