Re: PATCH: logical_work_mem and logical streaming of large in-progress transactions
Amit Kapila <amit.kapila16@gmail.com>
Commits
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the thread's linked commits as JSON, with link sources.
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 Tue, Oct 22, 2019 at 10:42 PM Tomas Vondra <tomas.vondra@2ndquadrant.com> wrote: > > On Tue, Oct 22, 2019 at 10:30:16AM +0530, Dilip Kumar wrote: > > > >I have moved it out as a separate patch (0003) so that if we need that > >we need this for the streaming transaction then we can keep this. > >> > > I'm OK with moving it to a separate patch. That being said I think > ability to control memory usage for individual subscriptions is very > useful. Saying "We don't need such parameter" is essentially equivalent > to saying "One size fits all" and I think we know that's not true. > > Imagine a system with multiple subscriptions, some of them mostly > replicating OLTP changes, but one or two replicating tables that are > updated in batches. What we'd have is to allow higher limit for the > batch subscriptions, but much lower limit for the OLTP ones (which they > should never hit in practice). > This point is not clear to me. The changes are recorded in ReorderBuffer which doesn't have any filtering aka it will have all the changes irrespective of the subscriber. How will it make a difference to have different limits? > With a single global GUC, you'll either have a high value - risking > OOM when the OLTP subscriptions happen to decode a batch update, or a > low value affecting the batch subscriotions. > > It's not strictly necessary (and we already have such limit), so I'm OK > with treating it as an enhancement for the future. > I am fine too if its usage is clear. I might be missing something here. -- With Regards, Amit Kapila. EnterpriseDB: http://www.enterprisedb.com