On Fri, Mar 11, 2011 at 09:03:33AM -0500, Robert Haas wrote: > On Fri, Mar 11, 2011 at 8:21 AM, Fujii Masao <masao.fu...@gmail.com> wrote: > > > > In that case, the last write WAL timestamp would become equal to the > > last replay WAL timestamp. So we can see that there is no lag. > > Oh, I see (I think). You're talking about write/replay lag, but I was > thinking of master/slave transmission lag. >
Which are both useful numbers to know: the first tells you how "stale" queries from a Hot Standby will be, the second tells you the maximum data loss from a "meteor hits the master" scenario where that slave is promoted, if I understand all the interactions correctly. Ross -- Ross Reedstrom, Ph.D. reeds...@rice.edu Systems Engineer & Admin, Research Scientist phone: 713-348-6166 Connexions http://cnx.org fax: 713-348-3665 Rice University MS-375, Houston, TX 77005 GPG Key fingerprint = F023 82C8 9B0E 2CC6 0D8E F888 D3AE 810E 88F0 BEDE -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
