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 Sun, Mar 29, 2020 at 6:29 AM Tomas Vondra <tomas.vondra@2ndquadrant.com> wrote: > > On Sat, Mar 28, 2020 at 03:29:34PM +0530, Amit Kapila wrote: > >On Sat, Mar 28, 2020 at 2:19 PM Dilip Kumar <dilipbalaut@gmail.com> wrote: > > > >How about if instead of writing an XLOG_XACT_ASSIGNMENT WAL, we set a > >flag in TransactionStateData and then log that as special information > >whenever we write next WAL record for a new subtransaction? Then > >during recovery, we can only call ProcArrayApplyXidAssignment when we > >find that special flag is set in a WAL record. One idea could be to > >use a flag bit in XLogRecord.xl_info. If that is feasible then the > >solution can work as it is now, without any overhead or change in the > >way we maintain KnownAssignedXids. > > > > Ummm, how is that different from what the patch is doing now? I mean, we > only write the top-level XID for the first WAL record in each subxact, > right? Or what would be the difference with your approach? > We have to do what the patch is currently doing and additionally, we will set this flag after PGPROC_MAX_CACHED_SUBXIDS which would allow us to call ProcArrayApplyXidAssignment during WAL replay only after PGPROC_MAX_CACHED_SUBXIDS number of subxacts. It will help us in clearing the KnownAssignedXids at the same time as we do now, so no additional performance overhead. -- With Regards, Amit Kapila. EnterpriseDB: http://www.enterprisedb.com