Horton

Re: TupleTableSlot abstraction

Michael Paquier <michael@paquier.xyz>

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From: Michael Paquier <michael@paquier.xyz>
To: Andres Freund <andres@anarazel.de>
Cc: Jeff Janes <jeff.janes@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>, Robert Haas <robertmhaas@gmail.com>, Haribabu Kommi <kommi.haribabu@gmail.com>, Amit Khandekar <amitdkhan.pg@gmail.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Amit Kapila <amit.kapila16@gmail.com>
Date: 2019-02-27T06:34:07Z
Lists: pgsql-hackers 
On Tue, Feb 26, 2019 at 09:42:38PM -0800, Andres Freund wrote:
> I'm not so sure that's the architecturally correct fix however. Is it
> actually guaranteed, given expanded tuples, toasting, etc, that there's
> no other memory leak here? I wonder if we shouldn't work twoards using a
> short lived memory context here. Note how e.g. printtup() uses a short
> lived context for its work.

Perhaps.  I got to wonder if this change would not impact code using
their own DestReceiver, resulting in similar leaks when they insert
tuples on-the-fly.  Such issues can be surprising for fork an plugin
developers.  I was playing a bit with some refactoring of relation
creation for CTAS in the scope of temporary matviews, and noticed this
issue on the CF list, so that was a bit annoying, and issues like that
tend to be easily forgotten..
--
Michael

Commits

  1. Fix memory leak when inserting tuple at relation creation for CTAS

  2. Build HashState's hashkeys expression with the correct parent.

  3. Move TupleTableSlots boolean member into one flag variable.

  4. Move generic slot support functions from heaptuple.c into execTuples.c.

  5. Remove absolete function TupleDescGetSlot().

  6. Remove function list from prologue of execTuples.c.

  7. Split ExecStoreTuple into ExecStoreHeapTuple and ExecStoreBufferHeapTuple.

  8. Change TupleTableSlot->tts_nvalid to type AttrNumber.

  9. Deduplicate code between slot_getallattrs() and slot_getsomeattrs().

  10. Mention ownership requirements for REFRESH MATERIALIZED VIEW in docs

  11. Spell "partitionwise" consistently.

  12. Fix WHERE CURRENT OF when the referenced cursor uses an index-only scan.