Re: Idea for improving buildfarm robustness

Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
> On 09/29/2015 02:48 PM, Tom Lane wrote:
>> Also, perhaps we'd only enable this behavior in --enable-cassert builds,
>> to avoid any risk of a postmaster incorrectly choosing to suicide in a
>> production scenario. Or maybe that's overly conservative.

> Not every buildfarm member uses cassert, so I'm not sure that's the best
> way to go. axolotl doesn't, and it's one of those that regularly has
> speed problems. Maybe a not-very-well-publicized GUC, or an environment
> setting? Or maybe just enable this anyway. If the data directory is gone
> what's the point in keeping the postmaster around? Shutting it down
> doesn't seem likely to cause any damage.

The only argument I can see against just turning it on all the time is
the possibility of false positives. I mentioned ENFILE and EPERM as
foreseeable false-positive conditions, and I'm worried that there might be
others. It might be good if we have a small list of specific errnos that
cause us to conclude we should die, rather than a small list that cause us
not to. But as long as we're reasonably confident that we're seeing an
error that means somebody deleted pg_control, I think abandoning ship
is just fine.

regards, tom lane