George Pavlov wrote: > Based on how it works it seems that a server crash might lose the > in-memory stats data as well? Yeah, IIRC the postmaster removes the stat file after crash recovery. It doesn't check the file for correctness. > I imagine PITR does not take care of that special file (where is it > by, by the way?). I have not worked with replication (yet), but I > imagine replica databases will also be agnostic of the master's stats? Neither PITR nor the replication systems I know about do anything about the stats. The file is $PGDATA/global/pgstat.stat The code to read it, which is at the same time the documentation to its format, is in src/backend/postmaster/pgstat.c, function pgstat_read_statfile. It's quite simple. I think you could read it in Perl if you wanted; and rewrite the file again after a restore (you'd need to change the Oids in the table entries, etc). -- Alvaro Herrera http://www.CommandPrompt.com/ The PostgreSQL Company - Command Prompt, Inc.
