On 2014-04-28 10:03:58 -0400, Tom Lane wrote: > What I find much more worrisome about Andres' proposals is that he > seems to be thinking that there are *no* other changes to the buffer > headers on the horizon.
Err. I am not thinking that at all. I am pretty sure I never made that argument. The reason I want to limit the number of connections is it allows *both*, shrinking the size of BufferDescs due to less alignment padding *and* stuffing the refcount and flags into one integer. > That's untenable. And I don't want to be told that we can't improve > the buffer management algorithms because adding another field would > make the headers not fit in a cacheline. I think we need to move some less frequently fields to a separate array to be future proof. Heikki suggested freeNext, wait_backend_pid I added io_in_progress_lock. We could theoretically replace buf_id by calculating it based on the BufferDescriptors array, but that's probably not a good idea. Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, 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
