Horton

Re: PATCH: logical_work_mem and logical streaming of large in-progress transactions

Tomas Vondra <tomas.vondra@2ndquadrant.com>

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From: Tomas Vondra <tomas.vondra@2ndquadrant.com>
To: Alexey Kondratov <a.kondratov@postgrespro.ru>, Peter Eisentraut <peter.eisentraut@2ndquadrant.com>, Erik Rijkers <er@xs4all.nl>
Cc: Masahiko Sawada <sawada.mshk@gmail.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>, Konstantin Knizhnik <k.knizhnik@postgrespro.ru>
Date: 2019-01-14T18:23:31Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Tighten the concurrent abort check during decoding.

  2. Improve hash_create()'s API for some added robustness.

  3. Use HASH_BLOBS for xidhash.

  4. Fix initialization of RelationSyncEntry for streaming transactions.

  5. Remove unused function declaration in logicalproto.h.

  6. Add additional tests to test streaming of in-progress transactions.

  7. Fix inline marking introduced in commit 464824323e.

  8. Add support for streaming to built-in logical replication.

  9. Fix the SharedFileSetUnregister API.

  10. Fix comment in procarray.c

  11. Suppress compiler warning in non-cassert builds.

  12. Extend the BufFile interface.

  13. Mark a few logical decoding related variables with PGDLLIMPORT.

  14. Implement streaming mode in ReorderBuffer.

  15. Extend the logical decoding output plugin API with stream methods.

  16. WAL Log invalidations at command end with wal_level=logical.

  17. Immediately WAL-log subtransaction and top-level XID association.

  18. Allow logical replication to transfer data in binary format.

  19. Only superuser can set sslcert/sslkey in postgres_fdw user mappings

  20. Track statistics for spilling of changes from ReorderBuffer.

  21. Add logical_decoding_work_mem to limit ReorderBuffer memory usage.

  22. logical decoding: process ASSIGNMENT during snapshot build

  23. Emit invalidations to standby for transactions without xid.

Attachments

Hi,

Attached is an updated patch series, merging fixes and changes to TAP
tests proposed by Alexey. I've merged the fixes into the appropriate
patches, and I've kept the TAP changes / new tests as separate patches
towards the end of the series.

I'm a bit unhappy with two aspects of the current patch series:

1) We now track schema changes in two ways - using the pre-existing
schema_sent flag in RelationSyncEntry, and the (newly added) flag in
ReorderBuffer. While those options are used for regular vs. streamed
transactions, fundamentally it's the same thing and so having two
competing ways seems like a bad idea. Not sure what's the best way to
resolve this, though.

2) We've removed quite a few asserts, particularly ensuring sanity of
cmin/cmax values. To some extent that's expected, because by allowing
decoding of in-progress transactions relaxes some of those rules. But
I'd be much happier if some of those asserts could be reinstated, even
if only in a weaker form.


regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services