On Tue, Mar 21, 2017 at 10:21 AM, Alvaro Herrera <alvhe...@2ndquadrant.com> wrote: > Robert Haas wrote: >> On Tue, Mar 21, 2017 at 10:01 AM, Amit Kapila <amit.kapil...@gmail.com> >> wrote: > >> > Sure, we can try that. I think we need to try it with >> > synchronous_commit = off, otherwise, WAL writes completely overshadows >> > everything. >> >> synchronous_commit = off is a much more realistic scenario than fsync = off. > > Sure, synchronous_commit=off is a reasonable case. But I say if we lose > a few % on the case where you update only the first indexed of a large > number of very wide columns all indexed, and this is only noticeable if > you don't write WAL and only if you update all the rows in the table, > then I don't see much reason for concern.
If the WAL writing hides the loss, then I agree that's not a big concern. But if the loss is still visible even when WAL is written, then I'm not so sure. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
