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: Amit Kapila <amit.kapila16@gmail.com>
Cc: Erik Rijkers <er@xs4all.nl>, 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: 2020-07-05T15:07:18Z
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, Jun 30, 2020 at 10:13 AM Dilip Kumar <dilipbalaut@gmail.com> wrote:
>
> On Tue, Jun 30, 2020 at 9:20 AM Amit Kapila <amit.kapila16@gmail.com> wrote:
> >
> > On Mon, Jun 29, 2020 at 4:24 PM Dilip Kumar <dilipbalaut@gmail.com> wrote:
> > >
> > > On Mon, Jun 22, 2020 at 4:30 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
> > > >
> > > >
> > > > Other than above tests, can we somehow verify that the invalidations
> > > > generated at commit time are the same as what we do with this patch?
> > > > We have verified with individual commands but it would be great if we
> > > > can verify for the regression tests.
> > >
> > > I have verified this using a few random test cases.  For verifying
> > > this I have made some temporary code changes with an assert as shown
> > > below.  Basically, on DecodeCommit we call
> > > ReorderBufferAddInvalidations function only for an assert checking.
> > >
> > > -void
> > >  ReorderBufferAddInvalidations(ReorderBuffer *rb, TransactionId xid,
> > >                                                           XLogRecPtr
> > > lsn, Size nmsgs,
> > > -
> > > SharedInvalidationMessage *msgs)
> > > +
> > > SharedInvalidationMessage *msgs, bool commit)
> > >  {
> > >         ReorderBufferTXN *txn;
> > >
> > >         txn = ReorderBufferTXNByXid(rb, xid, true, NULL, lsn, true);
> > > -
> > > +       if (commit)
> > > +       {
> > > +               Assert(txn->ninvalidations == nmsgs);
> > > +               return;
> > > +       }
> > >
> > > The result is that for a normal local test it works fine.  But with
> > > regression suit, it hit an assert at many places because if the
> > > rollback of the subtransaction is involved then at commit time
> > > invalidation messages those are not logged whereas with command time
> > > invalidation those are logged.
> > >
> >
> > Yeah, somehow, we need to ignore rollback to savepoint tests and
> > verify for others.
>
> Yeah, I have run the regression suite,  I can see a lot of failure
> maybe we can somehow see the diff and confirm that all the failures
> are due to rollback to savepoint only.  I will work on this.

I have compared the changes logged at command end vs logged at commit
time.  I have ignored the invalidation for the transaction which has
any aborted subtransaction in it.  While testing this I found one
issue, the issue is that if there are some invalidation generated
between last command counter increment and the commit transaction then
those were not logged.  I have fixed the issue by logging the pending
invalidation in RecordTransactionCommit.  I will include the changes
in the next patch set.

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