On 11/11/16 16:03, Francisco Olarte wrote: > On Fri, Nov 11, 2016 at 4:40 AM, 余森彬 <justdoit920...@gmail.com> wrote: >> As we know, the synchronous commit process is blocked while receives >> from acknowledgement from standby in >> PostgreSQL.This is good for data consistence in master and standby, and >> application can get important data from standby.But >> when the standby crash or network goes wrong, the master could be hang.Is >> there a feature plan for a semi sync like MySQL >> InnoDB(set a timer, and become asynchronous when timeout)? > > JMO, but it seems this basically means any process should be dessigned > to cope with the posibility of not having replicated data after > commit, so, why bother with synchronous replication in the first > place?
It's often more acceptable to say "we lose data when 2 servers die (or are in problems)" than "we lose data when 1 server dies" and it's also more acceptable to say "we stop answering when we lose 2 servers" but not "we stop answering when we lose 1 server", and semisync replication works for combination of these two. -- Petr Jelinek 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
