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Postgres FD Implementation
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  1. 17 Mar, 2019 2 commits
  3. 16 Mar, 2019 10 commits
  5. 15 Mar, 2019 6 commits
    • Tom Lane's avatar
      Further reduce memory footprint of CLOBBER_CACHE_ALWAYS testing. · d3f48dfa
      Tom Lane authored 
      Some buildfarm members using CLOBBER_CACHE_ALWAYS have been having OOM
problems of late.  Commit 2455ab48 addressed this problem by recovering
space transiently used within RelationBuildPartitionDesc, but it turns
out that leaves quite a lot on the table, because other subroutines of
RelationBuildDesc also leak memory like mad.  Let's move the temp-context
management into RelationBuildDesc so that leakage from the other
subroutines is also recovered.

I examined this issue by arranging for postgres.c to dump the size of
MessageContext just before resetting it in each command cycle, and
then running the update.sql regression test (which is one of the two
that are seeing buildfarm OOMs) with and without CLOBBER_CACHE_ALWAYS.
Before 2455ab48, the peak space usage with CCA was as much as 250MB.
That patch got it down to ~80MB, but with this patch it's about 0.5MB,
and indeed the space usage now seems nearly indistinguishable from a
non-CCA build.

RelationBuildDesc's traditional behavior of not worrying about leaking
transient data is of many years' standing, so I'm pretty hesitant to
change that without more evidence that it'd be useful in a normal build.
(So far as I can see, non-CCA memory consumption is about the same with
or without this change, whuch if anything suggests that it isn't useful.)
Hence, configure the patch so that we recover space only when
CLOBBER_CACHE_ALWAYS or CLOBBER_CACHE_RECURSIVELY is defined.  However,
that choice can be overridden at compile time, in case somebody would
like to do some performance testing and try to develop evidence for
changing that decision.

It's possible that we ought to back-patch this change, but in the
absence of back-branch OOM problems in the buildfarm, I'm not in
a hurry to do that.

Discussion: https://postgr.es/m/CA+TgmoY3bRmGB6-DUnoVy5fJoreiBJ43rwMrQRCdPXuKt4Ykaw@mail.gmail.com
      d3f48dfa
    • Peter Eisentraut's avatar
      PL/Tcl: Improve trigger tests organization · aefcc2bb
      Peter Eisentraut authored 
      The trigger tests for PL/Tcl were spread aroud pltcl_setup.sql and
pltcl_queries.sql, mixed with other tests, which makes them hard to
follow and edit.  Move all the trigger-related pieces to a new file
pltcl_trigger.sql.  This also makes the test setup more similar to
plperl and plpython.
      aefcc2bb
    • Peter Eisentraut's avatar
      Add walreceiver API to get remote server version · 69039fda
      Peter Eisentraut authored 
      Add a separate walreceiver API function walrcv_server_version() to get
the version of the remote server, instead of doing it as part of
walrcv_identify_system().  This allows the server version to be
available even for uses that don't call IDENTIFY_SYSTEM, and it seems
cleaner anyway.

This is for an upcoming patch, not currently used.
Reviewed-by: default avatarMichael Paquier <michael@paquier.xyz>
Discussion: https://www.postgresql.org/message-id/20190115071359.GF1433@paquier.xyz
      69039fda
    • Michael Paquier's avatar
      Fix typo related to to_tsvector() in tests of json and jsonb · 4e197bf1
      Michael Paquier authored 
      Author: Sho Kato
Reviewed-by: Kyotaro Horiguchi
Discussion: https://postgr.es/m/25C1C6B2E7BE044889E4FE8643A58BA963E1D03D@G01JPEXMBKW03
      4e197bf1
    • Thomas Munro's avatar
      Enable parallel query with SERIALIZABLE isolation. · bb16aba5
      Thomas Munro authored 
      Previously, the SERIALIZABLE isolation level prevented parallel query
from being used.  Allow the two features to be used together by
sharing the leader's SERIALIZABLEXACT with parallel workers.

An extra per-SERIALIZABLEXACT LWLock is introduced to make it safe to
share, and new logic is introduced to coordinate the early release
of the SERIALIZABLEXACT required for the SXACT_FLAG_RO_SAFE
optimization, as follows:

The first backend to observe the SXACT_FLAG_RO_SAFE flag (set by
some other transaction) will 'partially release' the SERIALIZABLEXACT,
meaning that the conflicts and locks it holds are released, but the
SERIALIZABLEXACT itself will remain active because other backends
might still have a pointer to it.

Whenever any backend notices the SXACT_FLAG_RO_SAFE flag, it clears
its own MySerializableXact variable and frees local resources so that
it can skip SSI checks for the rest of the transaction.  In the
special case of the leader process, it transfers the SERIALIZABLEXACT
to a new variable SavedSerializableXact, so that it can be completely
released at the end of the transaction after all workers have exited.

Remove the serializable_okay flag added to CreateParallelContext() by
commit 9da0cc35, because it's now redundant.

Author: Thomas Munro
Reviewed-by: Haribabu Kommi, Robert Haas, Masahiko Sawada, Kevin Grittner
Discussion: https://postgr.es/m/CAEepm=0gXGYhtrVDWOTHS8SQQy_=S9xo+8oCxGLWZAOoeJ=yzQ@mail.gmail.com
      bb16aba5
    • Amit Kapila's avatar
      During pg_upgrade, conditionally skip transfer of FSMs. · 13e8643b
      Amit Kapila authored 
      If a heap on the old cluster has 4 pages or fewer, and the old cluster
was PG v11 or earlier, don't copy or link the FSM. This will shrink
space usage for installations with large numbers of small tables.

This will allow pg_upgrade to take advantage of commit b0eaa4c5 where
we have avoided creation of the free space map for small heap relations.

Author: John Naylor
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/CACPNZCu4cOdm3uGnNEGXivy7Gz8UWyQjynDpdkPGabQ18_zK6g%40mail.gmail.com
      13e8643b
  7. 14 Mar, 2019 13 commits
  9. 13 Mar, 2019 9 commits