Horton

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

Dilip Kumar <dilipbalaut@gmail.com>

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From: Dilip Kumar <dilipbalaut@gmail.com>
To: Erik Rijkers <er@xs4all.nl>
Cc: Amit Kapila <amit.kapila16@gmail.com>, Kuntal Ghosh <kuntalghosh.2007@gmail.com>, Tomas Vondra <tomas.vondra@2ndquadrant.com>, Michael Paquier <michael@paquier.xyz>, Peter Eisentraut <peter.eisentraut@2ndquadrant.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2020-05-27T14:52:23Z
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

On Tue, May 26, 2020 at 7:45 AM Dilip Kumar <dilipbalaut@gmail.com> wrote:
>
> On Mon, May 25, 2020 at 8:48 PM Erik Rijkers <er@xs4all.nl> wrote:
> >
>
> > Hi,
> >
> > I am not able to extract all files correctly from this tar.
> >
> > The first file v24-0001-* seems to have some 'binary' junk at the top.
> >
> > (The other 11 files seem normally readably)
>
> Okay, sending again.

While reviewing/testing I have found a couple of problems in 0005 and
0006 which I have fixed in the attached version.

In 0005:  Basically, in the latest version, we are starting a stream
or begin txn only if there are any changes because we are doing in the
while loop, so we need to stream_stop/commit also if we have started
the stream.

In 0006: If we are streaming the serialized changed and there are
still few incomplete changes, then currently we are not deleting the
spilled file, but the spill file contains all the changes of the
transaction because there is no way to partially truncate it.  So in
the next stream, it will try to resend those.  I have fixed this by
sending the spilled transaction as soon as its changes are complete so
ideally, we can always delete the spilled file.  It is also a better
solution because this transaction is already spilled once and that
happened because we could not stream it,  so we better stream it on
the first opportunity that will reduce the replay lag which is our
whole purpose here.

-- 
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com