On Fri, Jun 12, 2015 at 7:27 PM, Steve Kehlet <steve.kehlet@xxxxxxxxx> wrote: > Just wanted to report that I rolled back my VM to where it was with 9.4.2 > installed and it wouldn't start. I installed 9.4.4 and now it starts up just > fine: > >> 2015-06-12 16:05:58 PDT [6453]: [1-1] LOG: database system was shut down >> at 2015-05-27 13:12:55 PDT >> 2015-06-12 16:05:58 PDT [6453]: [2-1] LOG: MultiXact member wraparound >> protections are disabled because oldest checkpointed MultiXact 1 does not >> exist on disk >> 2015-06-12 16:05:58 PDT [6457]: [1-1] LOG: autovacuum launcher started >> 2015-06-12 16:05:58 PDT [6452]: [1-1] LOG: database system is ready to >> accept connections >> done >> server started > > And this is showing up in my serverlog periodically as the emergency > autovacuums are running: > >> 2015-06-12 16:13:44 PDT [6454]: [1-1] LOG: MultiXact member wraparound >> protections are disabled because oldest checkpointed MultiXact 1 does not >> exist on disk > > **Thank you Robert and all involved for the resolution to this.** > >> With the fixes introduced in this release, such a situation will result in >> immediate emergency autovacuuming until a correct oldestMultiXid value can >> be determined > > Okay, I notice these vacuums are of the "to prevent wraparound" type (like > VACUUM FREEZE), that do hold locks preventing ALTER TABLEs and such. Good to > know, we'll plan our software updates accordingly. > > Is there any risk until these autovacuums finish? As long as you see only a modest number of files in pg_multixact/members, you're OK. But in theory, until that emergency autovacuuming finishes, there's nothing keeping that directory from wrapping around. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
