On Fri, Jun 23, 2023 at 12:39 PM Dilip Kumar <dilipbal...@gmail.com> wrote: > > On Fri, Jun 9, 2023 at 10:47 AM Masahiko Sawada <sawada.m...@gmail.com> wrote: > > > > Hi, > > > > In logical decoding, we don't need to collect decoded changes of > > aborted transactions. While streaming changes, we can detect > > concurrent abort of the (sub)transaction but there is no mechanism to > > skip decoding changes of transactions that are known to already be > > aborted. With the attached WIP patch, we check CLOG when decoding the > > transaction for the first time. If it's already known to be aborted, > > we skip collecting decoded changes of such transactions. That way, > > when the logical replication is behind or restarts, we don't need to > > decode large transactions that already aborted, which helps improve > > the decoding performance. > > > +1 for the idea of checking the transaction status only when we need > to flush it to the disk or send it downstream (if streaming in > progress is enabled). Although this check is costly since we are > planning only for large transactions then it is worth it if we can > occasionally avoid disk or network I/O for the aborted transactions. >
Thanks. I've attached the updated patch. With this patch, we check the transaction status for only large-transactions when eviction. For regression test purposes, I disable this transaction status check when logical_replication_mode is set to 'immediate'. Regards, -- Masahiko Sawada Amazon Web Services: https://aws.amazon.com
v2-0001-Skip-decoding-already-aborted-transactions.patch
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