Fujii Masao <masao(dot)fujii(at)gmail(dot)com> writes:
> The problem is that fsync needs to be issued too frequently, which would
> be harmless in asynchronous replication, but not in synchronous one.
> A transaction would have to wait for the primary's and standby's fsync
> before returning a "success" to a client.
Surely that is exactly what is *required* if the user has asked for
synchronous replication.
regards, tom lane