Re: crash with assertions and WAL_DEBUG

Andres Freund wrote:
> On 2014-06-14 16:57:33 -0400, Tom Lane wrote:
> > Alvaro Herrera <alvherre@2ndquadrant.com> writes:
> > > I noticed that HEAD crashes at startup with assertions disabled and
> > > WAL_DEBUG turned on:
> > 
> > I'm beginning to think we're going to have to give up on that
> > no-pallocs-in-critical-sections Assert.  It was useful to catch
> > unnecessarily-dangerous allocations in mainline cases, but getting rid
> > of every last corner-case palloc is looking to be, if not impossible,
> > at least a lot more trouble than it is worth.
> 
> I think we at least need to remove it from 9.4. We shouldn't release
> with an assertion that still regularly triggers in more or less
> 'harmless' situations.

Yeah, removing it in 9.4 is likely a good idea -- we have an open item
about it in connection with LWLOCK_DEBUG, and now this.  Who knows what
other debugging features will cause trouble.

> I think it might be worthwile to keep it in master to help maintain the
> rule against allocations in critical sections. And perhaps as a reminder
> that e.g. the checkpointer is doing bad things...

I also agree with keeping it in 9.5.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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