Merlin Moncure wrote: > After last night, I rebuilt the cluster, turning on checksums, turning > on synchronous commit (it was off) and added a standby replica. This > should help narrow the problem down should it re-occur; if storage is > bad (note, other database on same machine is doing 10x write activity > and is fine) or something is scribbling on shared memory (my guess > here) then checksums should be popped, right?
Not really sure about that. As I recall we compute the CRC on the buffer's way out, based on the then-current contents, so if something scribbles on the buffer while it's waiting to be evicted, the CRC computation would include the new (corrupted) bytes rather than the original ones -- see FlushBuffer. -- Álvaro Herrera https://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