Re: can postgres run well on NFS mounted partitions?

On Thu, Nov 12, 2015 at 12:49 PM, Scott Marlowe <scott(dot)marlowe(at)gmail(dot)com>
wrote:

> On Thu, Nov 12, 2015 at 11:19 AM, anj patnaik <patna73(at)gmail(dot)com> wrote:
> > The Linux VM where postgres is running over NFS is in a different
> location
> > than where I am. Both the NFS mounted storage and VM are on the same
> network
> > connected via 1GB ethernet switch.
> >
> > The physical server for the Linux VM has UPS.
> >
> > Is there any specific test I can run to do power failure?
> >
> > Can I reboot my VM to test this or that wouldn't be good enough?
> >
> > Also, why does a checkpoint need to run? I used the graphical installer
> to
> > install postgres so I assume it would start automatically when the server
> > starts.
> >
> > I was also thinking of blackhole testing. If I do a blackhole to the NFS
> > server would I be able to test this accurately?
> >
> > Folks in the other teams believe NFS should work fine for us so I need to
> > check it out.
> >
> > Your ideas are highly appreciated!
>
> The point of the checkpoint is to make sure as much as possible is
> being written to the data directory when you "pull the plug". But
> without being able to pull the power plugs on the NAS or db server you
> can't really test for reliability in case of power loss. So you can't
> know that it'll survive one. Just disconnecting its network connection
> etc means it can still write out cached data if it isn't properly
> syncing it.
>

All of the above make we curious about using NFS for the data files, but
having the WAL files on a local, perhaps SSD, device.​ I am not
knowledgeable about WAL. Of course, I don't know why the OP wants to put
the database files on an NFS.

--

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