Hi, On Thu, Dec 4, 2008 at 6:29 PM, Simon Riggs <[EMAIL PROTECTED]> wrote: > The only sensible settings are > synchronous_commit = on, synchronous_replication = on > synchronous_commit = on, synchronous_replication = off > synchronous_commit = off, synchronous_replication = off > > This doesn't make any sense: (does it??) > synchronous_commit = off, synchronous_replication = on
If the standby replies before writing the WAL, that strategy can improve the performance with moderate reliability, and sounds sensible. IIRC, MySQL Cluster might use that strategy. > I was expecting you to have walreceiver and startup share an end of WAL > address via shared memory, so that startup never tries to read past end. > That way we would be able to begin reading a WAL file *before* it was > filled. Waiting until a file fills means we still have to have > archive_timeout set to ensure we switch regularly. You mean that not pg_standby but startup process waits for the next WAL available? If so, I agree with you in the future. That is, I just think that this is next TODO because there are many problems which we should resolve carefully to achieve it. But, if it's essential for 8.4, I will tackle it. What is your opinion? I'd like to clear up the goal for 8.4. Regards, -- Fujii Masao NIPPON TELEGRAPH AND TELEPHONE CORPORATION NTT Open Source Software Center -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
