Mike Schanne <mschanne@xxxxxxx> writes: > Is this what you are referring to? > - Prevent VACUUM from trying to freeze an old multixact ID involving a still-running transaction (Nathan Bossart, Jeremy Schneider) > This case would lead to VACUUM failing until the old transaction terminates. > https://www.postgresql.org/docs/release/9.6.16/ Hmmm ... after digging through the commit log, it seems the improvements I was thinking of were all pre-9.6. The only post-9.6 vacuum truncation performance fix I can find is https://git.postgresql.org/gitweb/?p=postgresql.git&a=commitdiff&h=7e26e02ee which came in in v10. regards, tom lane
