Koichi Suzuki wrote: > I've once proposed a patch for 64bit transaction ID, but this causes > some overhead to each tuple (XMIN and XMAX). Pgbench with 64bit > transaction ID has to pay about a couple of percent of performance. If > 64bit transaction ID is a reasonable fix, I've already posted this > patch. Anyone can apply this to later versions.
Be careful, the pg_multixact stuff assumes that a MultiXactId is the same size as TransactionId, so you have to change that too. I don't recall offhand if it was defined in a way that would make it "just work" automatically. (You'd also have to be careful about it not overrunning the SLRU files when it's close to the end of 'em.). -- Alvaro Herrera http://www.CommandPrompt.com/ The PostgreSQL Company - Command Prompt, Inc. ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
