Timeout for asynchronous replication Re: Timeout and wait-forever in sync rep
Fujii Masao <masao.fujii@gmail.com>
From: Fujii Masao <masao.fujii@gmail.com>
To: PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2010-12-06T07:51:30Z
Lists: pgsql-hackers
Attachments
- replication_timeout_v1.patch (application/octet-stream) patch v1
On Mon, Dec 6, 2010 at 3:42 PM, Fujii Masao <masao.fujii@gmail.com> wrote: > On Fri, Oct 15, 2010 at 9:41 PM, Fujii Masao <masao.fujii@gmail.com> wrote: >> The timeout doesn't oppose to 'wait-forever'. Even if you choose 'wait >> -forever' (i.e., you set allow_standalone_master to false), the master >> should detect the standby crash as soon as possible by using the >> timeout. For example, imagine that max_wal_senders is set to one and >> the master cannot detect the standby crash because of absence of the >> timeout. In this case, even if you start new standby, it will not be >> able to connect to the master since there is no free walsender slot. >> As the result, the master actually waits forever. > > This occurred to me that the timeout would be required even for > asynchronous streaming replication. So, how about implementing the > replication timeout feature before synchronous replication itself? Here is the patch. This is one of features required for synchronous replication, so I added this into current CF as a part of synchronous replication. Regards, -- Fujii Masao NIPPON TELEGRAPH AND TELEPHONE CORPORATION NTT Open Source Software Center