On 08/15/2017 09:55 PM, Robert Haas wrote:
> On Tue, Aug 15, 2017 at 3:42 PM, Tomas Vondra
> <tomas.vondra@2ndquadrant.com> wrote:
>> What I think we should not do is interpret the bitmasks (omitting some of
>> the information) assuming all the bits were set correctly.
>
> I'm still confused. HEAP_XMIN_COMMITTED|HEAP_XMIN_ABORTED ==
> HEAP_XMIN_FROZEN. Nobody is proposing to omit anything; to the
> contrary, what's being proposed is not to display the same thing
> twice (and in a misleading fashion, to boot).
>
I understand your point. Assume you're looking at this bit of code:
if (HeapTupleHeaderXminCommitted(enumval_tup->t_data)) return;
which is essentially
if (enumval_tup->t_data & HEAP_XMIN_COMMITTED) return;
If the function only gives you HEAP_XMIN_FROZEN, how likely is it you
miss this actually evaluates as true?
You might say that people investigating issues in this area of code
should be aware of how HEAP_XMIN_FROZEN is defined, and perhaps you're
right ...
regards
--
Tomas Vondra http://www.2ndQuadrant.com
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