Jeff Janes <jeff.ja...@gmail.com> wrote: > Kevin Grittner <kgri...@ymail.com> wrote:
>> So reducing vacuum_freeze_min_age not only helps minimize the >> writes that are needed when autovacuum needs to scan the entire >> heap, > > How does it do that? If the tuple doesn't need to frozen now > because it was already frozen, that just means the write happened > at a different time but it still happened. There's a lot to be said for nibbling away at it during VM autovacuum runs versus doing it in big chunks in heap-scan runs, particularly if your BBU cache can absorb up to a certain amout with no real pain, but causes major pain if the write cache fills. -Kevin -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers