Re: logical decoding : exceeded maxAllocatedDescs for .spill files

Noah Misch <noah(at)leadboat(dot)com> writes:
> On Thu, Jan 09, 2020 at 12:45:41AM -0500, Tom Lane wrote:
>> (1) Why did we get a crash and not some more-decipherable out-of-resources
>> error? Can we improve that experience?

> By default, 32-bit AIX binaries have maxdata:0x00000000. Specifying
> maxdata:0x10000000 provides the same 256M of RAM, yet it magically changes the
> SIGSEGV to ENOMEM:
> ...
> We could add -Wl,-bmaxdata:0x10000000 (or a higher value) to LDFLAGS when
> building for 32-bit AIX.

+1, seems like that would improve matters considerably on that platform.

>> (2) Should we be dialing back the resource consumption of this test?
>> Even on machines where it doesn't fail outright, I'd imagine that it's
>> costing a lot of buildfarm cycles. Is it actually worth that?

> The test's resource usage, being quite low, should not be a factor in the
> test's fate. On my usual development machine, the entire
> 006_logical_decoding.pl file takes just 3s and ~250 MiB of RAM.

Yeah, as I noted downthread, it appears that initdb itself can't
succeed with less than ~250MB these days. My old-school self
feels like that's excessive, but I must admit I'm not motivated
to go reduce it right now. But I think it's a clear win to fail
with "out of memory" rather than "SIGSEGV", so I think we ought
to adjust the AIX build options as you suggest.

regards, tom lane