On 12 December 2014 at 18:04, Bruce Momjian <br...@momjian.us> wrote:
> Well, it seems we need to see some actual cases where compression does > help before moving forward. I thought Amit had some amazing numbers for > WAL compression --- has that changed? For background processes, like VACUUM, then WAL compression will be helpful. The numbers show that only applies to FPWs. I remain concerned about the cost in foreground processes, especially since the cost will be paid immediately after checkpoint, making our spikes worse. What I don't understand is why we aren't working on double buffering, since that cost would be paid in a background process and would be evenly spread out across a checkpoint. Plus we'd be able to remove FPWs altogether, which is like 100% compression. -- Simon Riggs 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
