On 18 April 2017 at 18:55, Masahiko Sawada <sawada.m...@gmail.com> wrote: > Hi, > > As doc of logical decoding said as a note[1], logical replication can > support the synchronous replication with some restriction. But In > addition to this, IIUC in logical replication decoded data is sent to > subscribers only when the commit WAL record is decoded (calls > ReorderBufferCommit) .
Correct. > It means that the local SQL execution and > applying the decoded data on subscriber side are always executed in a > sequential order, and the response time can simply be doubled or even > more (OTOH a good point is that decoded data of aborted transaction is > never sent to subscriber). I think there will be a lot of peoples who > want to use logical synchronous replication but this is a big > restriction for such user. I think we should document it or deal with > it. > Thought? Definitely should be documented. I think it's covered under logical decoding, but needs at least an xref. -- Craig Ringer http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
