Re: pgsql: Reduce spurious Hot Standby conflicts from never-visible records - Mailing list pgsql-committers

From Tom Lane
Subject Re: pgsql: Reduce spurious Hot Standby conflicts from never-visible records
Date
Msg-id 27713.1292008864@sss.pgh.pa.us
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In response to pgsql: Reduce spurious Hot Standby conflicts from never-visible records  (Simon Riggs <simon@2ndQuadrant.com>)
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Simon Riggs <simon@2ndQuadrant.com> writes:
> Reduce spurious Hot Standby conflicts from never-visible records.
> Hot Standby conflicts only with tuples that were visible at
> some point. So ignore tuples from aborted transactions or for
> tuples updated/deleted during the inserting transaction when
> generating the conflict transaction ids.

> Following detailed analysis and test case by Noah Misch.
> Original report covered btree delete records, correctly observed
> by Heikki Linnakangas that this applies to other cases also.
> Fix covers all sources of cleanup records via common code.
> Includes additional fix compared to commit on HEAD

ISTM HeapTupleHeaderAdvanceLatestRemovedXid is still pretty broken,
in that it's examining xmax without having checked that xmax is (a)
valid or (b) a lock rather than a deletion xmax.

            regards, tom lane

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