Re: pgsql: Avoid spurious deadlocks when upgrading a tuple lock

On 2019-Jun-14, Tom Lane wrote:

> I wrote:
> >> Hm, I don't get that warning. Does this patch silence it, please?
>
> > Uh, no patch attached? But initializing the variable where it's
> > declared would certainly silence it.
>
> BTW, after looking around a bit I wonder if this complaint isn't
> exposing an actual logic bug. Shouldn't skip_tuple_lock have
> a lifetime similar to first_time?

I think there are worse problems here. I tried the attached isolation
spec. Note that the only difference in the two permutations is that s0
finishes earlier in one than the other; yet the first one works fine and
the second one hangs until killed by the 180s timeout. (s3 isn't
released for a reason I'm not sure I understand.)

I don't think I'm going to have time to investigate this deeply over the
weekend, so I think the safest course of action is to revert this for
next week's set.

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