Re: Redesigning checkpoint_segments

On 6/5/2013 10:54 PM, Peter Geoghegan wrote:
> On Wed, Jun 5, 2013 at 10:27 PM, Joshua D. Drake <jd(at)commandprompt(dot)com> wrote:
>> I just wonder if we are looking in the right place (outside of some obvious
>> badness like the PANIC running out of disk space).
> So you don't think we should PANIC on running out of disk space? If
> you don't think we should do that, and you don't think that WAL
> writing should be throttled, what's the alternative?

As I mentioned in my previous email:

Instead of "running out of disk space PANIC" we should just write to an
emergency location within PGDATA and log very loudly that the SA isn't
paying attention. Perhaps if that area starts to get to an unhappy place
we immediately bounce into read-only mode and log even more loudly that
the SA should be fired. I would think read-only mode is safer and more
polite than an PANIC crash.

I do not think we should worry about filling up the hard disk except to
protect against data loss in the event. It is not user unfriendly to
assume that a user will pay attention to disk space. Really?

JD