Phil Frost wrote: > We are seeing an issue on RDS 9.4.5 where replica lag gets really high. > This lag seems to be correlated to a saturation of disk read throughput, > and vacuums of one of our larger and more frequently updated tables. > > I've heard that there's a bug where the replica will scan indexes > unnecessarily when doing the WAL replay when the vacuums happen. Can > anyone confirm this and maybe point me towards the commit where it was > fixed? Has there been a backport to the 9.4 series? Hi Phil, The 9.4 backport of the patch in question is this commit by yours truly: https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=30e3cb307d494990cb38cebff6bfc8b4ce27d7ab This will appear in the next minor release of the 9.4 series (as well as 9.5), due out sometime during February 2017. Thanks, -- Álvaro Herrera https://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-admin mailing list (pgsql-admin@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
