pgsql: Update docs to say you need fsync to make sync rep work fast.

Simon Riggs wrote:

Update docs to say you need fsync to make sync rep work fast.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/6e8e7cc580665ddd43c8ca2acc6d60f345570a57

This patch added this documentation text:

+    Replies are only sent when WAL is written to disk, so setting
+    <varname>fsync</> to <literal>off</> on the standby will significantly
+    reduce performance of synchronous replication and should be avoided.

Should we also issue a warning message in the server logs for the use of
fsync=off on the standby?

--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://enterprisedb.com

+ It's impossible for everything to be true. +

Bruce Momjian <bruce@momjian.us> writes:

Simon Riggs wrote:

Update docs to say you need fsync to make sync rep work fast.

Should we also issue a warning message in the server logs for the use of
fsync=off on the standby?

That patch was entirely wrong and has been reverted.

regards, tom lane