Paul Smith wrote: > With PostgreSQL 9.3.5 on Ubuntu 12.04, I'm getting the error: > > ERROR: MultiXactId 1934308693 has not been created yet -- apparent > wraparound > > on doing various queries on our database. I don't think it is a wraparound - > I think the tuple has mistakenly decided it has a MultiXactId related to it.
Yeah, that looks like the case. According to your pg_controldata output, you haven't used many multixacts at all: > Latest checkpoint's NextMultiXactId: 216 > Latest checkpoint's NextMultiOffset: 439 and the fact that you only have these files: > The pg_multixact directory contains two files > members/0000 > offsets/0000 confirms this. You XID counter is also rather low, only 24 million: > Latest checkpoint's NextXID: 0/24005839 so it doesn't seem plausible that the single bit HEAP_XMAX_IS_MULTI was turned on accidentally (something which I've never seen happen). It doesn't look like a randomly corrupt page either; normally you would see errors about mismatching page headers before you get to the point where Xmax is read. I wonder if the data page came from elsewhere. Maybe you copied a data file from another database? -- Álvaro Herrera http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, 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
