Re: pgsql: Add isolationtester spec for old heapam.c bug

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alvaro Herrera <alvherre@alvh.no-ip.org>
Cc: pgsql-committers@postgresql.org
Date: 2016-02-29T17:06:56Z
Lists: pgsql-hackers
I wrote:
> Alvaro Herrera <alvherre@alvh.no-ip.org> writes:
>> Add isolationtester spec for old heapam.c bug

> Hmmm ....

> http://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=spoonbill&dt=2016-02-27%2000%3A00%3A06

> This failure looks a lot like the timing-related problems I was chasing
> last week with deadlock-hard on the CLOBBER_CACHE_ALWAYS critters.
> spoonbill isn't CLOBBER_CACHE_ALWAYS, but it uses some weird malloc debug
> stuff that slows it down by similar orders of magnitude.  You seem to need
> to think about how to make this test less timing-dependent.

The plot thickens:

http://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=guaibasaurus&dt=2016-02-29%2016%3A17%3A01

guaibasaurus is not a particularly slow machine, and it's not using any
special build flags AFAICT.  So I'm not sure what to make of this case,
except that it proves the timing problem can manifest on normal builds.

			regards, tom lane


Commits

  1. Make new isolationtester test more stable

  2. Add isolationtester spec for old heapam.c bug