Re: pgsql: Avoid spurious deadlocks when upgrading a tuple lock - Mailing list pgsql-hackers

From Tom Lane
Subject Re: pgsql: Avoid spurious deadlocks when upgrading a tuple lock
Date
Msg-id 21723.1560615939@sss.pgh.pa.us
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In response to Re: pgsql: Avoid spurious deadlocks when upgrading a tuple lock  (Alvaro Herrera <alvherre@2ndquadrant.com>)
List pgsql-hackers
Alvaro Herrera <alvherre@2ndquadrant.com> writes:
> On 2019-Jun-14, Tom Lane wrote:
>> 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.)

Ugh.

> 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.

+1.  This is an old bug, we don't have to improve it for this release.

            regards, tom lane



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