Skip to content

P
Postgres FD Implementation
Switch branch/tag
  1. 16 May, 2018 2 commits
  3. 15 May, 2018 5 commits
  5. 14 May, 2018 5 commits
  7. 13 May, 2018 1 commit
  9. 12 May, 2018 1 commit
  11. 11 May, 2018 5 commits
  13. 10 May, 2018 1 commit
    • Teodor Sigaev's avatar
      Various improvements of skipping index scan during vacuum technics · 8e12f4a2
      Teodor Sigaev authored 
      - Change vacuum_cleanup_index_scale_factor GUC to PGC_USERSET.
  vacuum_cleanup_index_scale_factor GUC was defined as PGC_SIGHUP.  But this
  GUC affects not only autovacuum.  So it might be useful to change it from user
  session in order to influence manually runned VACUUM.
- Add missing tab-complete support for vacuum_cleanup_index_scale_factor
  reloption.
- Fix condition for B-tree index cleanup.
  Zero value of vacuum_cleanup_index_scale_factor means that user wants B-tree
  index cleanup to be never skipped.
- Documentation and comment improvements

Authors: Justin Pryzby, Alexander Korotkov, Liudmila Mantrova
Reviewed by: all authors and Robert Haas
Discussion: https://www.postgresql.org/message-id/flat/20180502023025.GD7631%40telsasoft.com
      8e12f4a2
  15. 09 May, 2018 13 commits
  17. 08 May, 2018 3 commits
    • Tom Lane's avatar
      Improve initdb's query for generating default descriptions a little. · dec10340
      Tom Lane authored 
      While poking into initdb's performance, I noticed that this query
wasn't being done very intelligently.  By forcing it to execute
obj_description() for each pg_proc/pg_operator join row, we were
essentially setting up a nestloop join to pg_description, which
is not a bright query plan when there are hundreds of outer rows.
Convert the check for a "deprecated" operator into a NOT EXISTS
so that it can be done as a hashed antijoin.  On my workstation
this reduces the time for this query from ~ 35ms to ~ 10ms.
Which is not a huge win, but it adds up over buildfarm runs.

In passing, insert forced query breaks (\n\n, in single-user mode)
after each SQL-query file that initdb sources, and after some
relatively new queries in setup_privileges().  This doesn't make
a lot of difference normally, but it will result in briefer, saner
error messages if anything goes wrong.
      dec10340
    • Peter Eisentraut's avatar
      Refine error messages · 831f5d11
      Peter Eisentraut authored 
      "JSON" when not referring to a data type should be upper case.
      831f5d11
    • Tom Lane's avatar
      Count heap tuples in non-SnapshotAny path in IndexBuildHeapRangeScan(). · 3a675f72
      Tom Lane authored 
      Brown-paper-bag bug in commit 7c91a036: when we rearranged the placement
of "reltuples += 1" statements, we missed including one in this code path.

The net effect of that was that CREATE INDEX CONCURRENTLY would set the
table's pg_class.reltuples to zero, as would index builds done during
bootstrap mode.  (It seems like parallel index builds ought to fail
similarly, but they don't, perhaps because reltuples is computed in some
other way.  You certainly couldn't figure that out from the abysmally
underdocumented parallelism code in this area.)

I was led to this by wondering why initdb seemed to have slowed down as
a result of 7c91a036, as is evident in the buildfarm's timing history.
The reason is that every system catalog with indexes had pg_class.reltuples
= 0 after bootstrap, causing the planner to make some terrible choices for
queries in the post-bootstrap steps.  On my workstation, this fix causes
the runtime of "initdb -N" to drop from ~2.0 sec to ~1.4 sec, which is
almost though not quite back to where it was in v10.  That's not much of
a deal for production use perhaps, but it makes a noticeable difference
for buildfarm and "make check-world" runs, which do a lot of initdbs.
      3a675f72
  19. 07 May, 2018 4 commits