Re: Transaction-controlled robustness for replication

On Tue, 2008-08-12 at 11:51 -0400, Bruce Momjian wrote:
> I think you need to make it an enumerated type like log_min_messages;
> something like:
>
> wal_transfer_wait

Yeh, that way sounds best and I like name.

> with values of:
>
> nothing: have network traffic send WAL as needed
> netflush: wait for flush of WAL network packets to slave
> process: wait for slave to process WAL traffic and
> optionally fsync

Suggest
async
syncnet
syncdisk

> The 'process' option either waits for fsync on the slave or not
> depending on how the slave is configured, meaning you could use
> synchronous_commit off to not wait for the fsync to disk.

Hmmm, not sure that flicking a switch on the standby should cause a loss
of performance on the master. That will be an accident waiting to
happen. Best to make all things that effect the performance/robustness
of the master be configuration options on the master side.

> I think we can add a table in the documention to show how to set things
> up in postgresql.conf for async master and async slave, and other
> combinations.

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Simon Riggs www.2ndQuadrant.com
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