Re: PATCH: logical_work_mem and logical streaming of large in-progress transactions
Amit Kapila <amit.kapila16@gmail.com>
Commits
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API reference →
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Tighten the concurrent abort check during decoding.
- 2ce353fc1902 14.0 landed
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Improve hash_create()'s API for some added robustness.
- b3817f5f7746 14.0 landed
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Use HASH_BLOBS for xidhash.
- a1b8aa1e4eec 14.0 landed
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Fix initialization of RelationSyncEntry for streaming transactions.
- 69bd60672af6 14.0 landed
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Remove unused function declaration in logicalproto.h.
- ddd5f6d2609b 14.0 landed
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Add additional tests to test streaming of in-progress transactions.
- 58b5ae9d62bd 14.0 landed
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Fix inline marking introduced in commit 464824323e.
- ac15b499f7f9 14.0 landed
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Add support for streaming to built-in logical replication.
- 464824323e57 14.0 landed
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Fix the SharedFileSetUnregister API.
- 4ab77697f67a 14.0 landed
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Fix comment in procarray.c
- 77c7267c37f7 14.0 cited
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Suppress compiler warning in non-cassert builds.
- e942af7b8261 14.0 cited
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Extend the BufFile interface.
- 808e13b282ef 14.0 landed
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Mark a few logical decoding related variables with PGDLLIMPORT.
- b48cac3b10a0 14.0 landed
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Implement streaming mode in ReorderBuffer.
- 7259736a6e5b 14.0 landed
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Extend the logical decoding output plugin API with stream methods.
- 45fdc9738b36 14.0 landed
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WAL Log invalidations at command end with wal_level=logical.
- c55040ccd017 14.0 landed
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Immediately WAL-log subtransaction and top-level XID association.
- 0bead9af484c 14.0 landed
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Allow logical replication to transfer data in binary format.
- 9de77b545313 14.0 cited
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Only superuser can set sslcert/sslkey in postgres_fdw user mappings
- cebf9d6e6ee1 13.0 cited
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Track statistics for spilling of changes from ReorderBuffer.
- 9290ad198b15 13.0 landed
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Add logical_decoding_work_mem to limit ReorderBuffer memory usage.
- cec2edfa7859 13.0 landed
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logical decoding: process ASSIGNMENT during snapshot build
- bac2fae05c77 13.0 cited
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Emit invalidations to standby for transactions without xid.
- c6ff84b06a68 9.6.0 cited
On Mon, Jan 6, 2020 at 3:56 PM Dilip Kumar <dilipbalaut@gmail.com> wrote:
>
> On Mon, Jan 6, 2020 at 2:11 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
> >
> > 3.
> > +static void
> > +ReorderBufferStreamTXN(ReorderBuffer *rb, ReorderBufferTXN *txn)
> > {
> > ..
> > + /*
> > + * If this is a subxact, we need to stream the top-level transaction
> > + * instead.
> > + */
> > + if (txn->toptxn)
> > + {
> > +
> > ReorderBufferStreamTXN(rb, txn->toptxn);
> > + return;
> > + }
> >
> > Is it ever possible that we reach here for subtransaction, if not,
> > then it should be Assert rather than if condition?
>
> ReorderBufferCheckMemoryLimit, can call it either for the
> subtransaction or for the main transaction, depends upon in which
> ReorderBufferTXN you are adding the current change.
>
That function has code like below:
ReorderBufferCheckMemoryLimit()
{
..
if (ReorderBufferCanStream(rb))
{
/*
* Pick the largest toplevel transaction and evict it from memory by
* streaming the already decoded part.
*/
txn = ReorderBufferLargestTopTXN(rb);
/* we know there has to be one, because the size is not zero */
Assert(txn && !txn->toptxn);
..
ReorderBufferStreamTXN(rb, txn);
..
}
How can it ReorderBufferTXN pass for subtransaction?
--
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com