Re: New sync commit mode remote_write

On Thu, Apr 19, 2012 at 2:47 AM, Robert Haas <robertmhaas@gmail.com> wrote:
> On Apr 19, 2012, at 5:05 AM, Magnus Hagander <magnus@hagander.net> wrote:
>> I admit to not having followed the discussion around the new mode for
>> synchronous_commit very closely, so my apologies if this has been
>> discussed and dismiseed - I blame failing to find it int he archives
>> ;)
>>
>> My understanding from looking at the docs is that
>> synchronous_commit=remote_write will always imply a *local* commit as
>> well.
>>
>> Is there any way to set the system up to do a write to the remote,
>> ensure it's in memory of the remote (remote_write mode, not full sync
>> to disk), but *not* necessarily to the local disk? Meaning we're ok to
>> release the transaction when the data is in memory both locally and
>> remotely but not wait for I/O?
>
> If we crash, the slave can end up ahead of the master, and then it's hopelessly corrupted...
>
> Maybe we could engineer around this, but it hasn't been done yet.

The work around would be for the master to refuse to automatically
restart after a crash, insisting on a fail-over instead (or a manual
forcing of recovery)?

Cheers,

Jeff