On 2014-05-12 19:14:55 +0300, Heikki Linnakangas wrote: > On 05/12/2014 06:26 PM, Andres Freund wrote: > >>>With the new "commit-in-progress" status in clog, we won't need the > >>>sub-committed clog status anymore. The "commit-in-progress" status will > >>>achieve the same thing. > >Wouldn't that cause many spurious waits? Because commit-in-progress > >needs to be waited on, but a sub-committed xact surely not? > > Ah, no. Even today, a subxid isn't marked as sub-committed, until you commit > the top-level transaction. The sub-commit state is a very transient state > during the commit process, used to make the commit of the sub-transactions > and the top-level transaction appear atomic. The commit-in-progress state > would be a similarly short-lived state. You mark the subxids and the top xid > as commit-in-progress just before the XLogInsert() of the commit record, and > you replace them with the real LSNs right after XLogInsert().
Ah, right. Forgot that detail... Greetings, Andres Freund -- Andres Freund 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