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

Amit Kapila <amit.kapila16@gmail.com>

From: Amit Kapila <amit.kapila16@gmail.com>
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>, Dilip Kumar <dilipbalaut@gmail.com>
Cc: Michael Paquier <michael@paquier.xyz>, Peter Eisentraut <peter.eisentraut@2ndquadrant.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2020-02-06T09:21:17Z
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.

On Wed, Feb 5, 2020 at 9:42 AM Dilip Kumar <dilipbalaut@gmail.com> wrote:
>
> >
> > I am not able to understand the change in
> > v8-0011-BUGFIX-set-final_lsn-for-subxacts-before-cleanup.  Do you have
> > any explanation for the same?
>
> It appears that in ReorderBufferCommitChild we are always setting the
> final_lsn of the subxacts so it should not be invalid.  For testing, I
> have changed this as an assert and checked but it never hit.  So maybe
> we can remove this change.
>

Tomas, do you remember anything about this change?  We are talking
about below change:

From: Tomas Vondra <tv@fuzzy.cz>
Date: Thu, 26 Sep 2019 19:14:45 +0200
Subject: [PATCH v8 11/13] BUGFIX: set final_lsn for subxacts before cleanup

---
 src/backend/replication/logical/reorderbuffer.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/backend/replication/logical/reorderbuffer.c
b/src/backend/replication/logical/reorderbuffer.c
index fe4e57c..beb6cd2 100644
--- a/src/backend/replication/logical/reorderbuffer.c
+++ b/src/backend/replication/logical/reorderbuffer.c
@@ -1327,6 +1327,10 @@ ReorderBufferCleanupTXN(ReorderBuffer *rb,
ReorderBufferTXN *txn)

  subtxn = dlist_container(ReorderBufferTXN, node, iter.cur);

+ /* make sure subtxn has final_lsn */
+ if (subtxn->final_lsn == InvalidXLogRecPtr)
+ subtxn->final_lsn = txn->final_lsn;
+

-- 
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com