Re: MultiXact member wraparound protections are disabled

Thanks. We started seeing this error right after a SAN FC re-cable effort - so yes, that would make sense.
We’ll do a little more digging to see if the 0000 could have gotten removed.
If that’s an older file that we have in our filesystem backups, is it safe to restore from there?

On 10/13/16, 3:30 PM, "Alvaro Herrera" <alvherre(at)2ndquadrant(dot)com> wrote:

>AnandKumar, Karthik wrote:
>> root(at)site-db01a:/var/lib/pgsql/cmates/data # ls pg_multixact/members
>> 0000 0001 0002 0003 0004 0005 0006 0007 0008 0009 000A 000B 000C 000D 000E 000F 0010 0011 0012 0013 0014 0015 0016 0017 0018 0019 001A 001B
>> root(at)site-db01a:/var/lib/pgsql/cmates/data # ls pg_multixact/offsets
>> 0001 0002 0003 0004 0005 0006 0007 0008 0009 000A 000B
>
>> postgres(at)site-db01a:~ $ /usr/pgsql-9.4/bin/pg_controldata /var/lib/pgsql/cmates/data
>
>> Latest checkpoint's NextMultiXactId: 784503
>> Latest checkpoint's NextMultiOffset: 1445264
>> Latest checkpoint's oldestMultiXid: 1
>> Latest checkpoint's oldestMulti's DB: 16457
>
>This looks perfectly normal, except that the pg_multixact/offsets/0000
>file is gone. oldestMultiXid is 1 so I don't see how could have the
>file gotten removed. Has this been upgraded recently from a previous
>9.3 or 9.4 version? There have been bugs in this area but they've been
>fixed now for some time.
>
>The 0000 file could have been removed manually, perhaps?
>
>--
>Álvaro Herrera https://www.2ndQuadrant.com/
>PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services