Tom Lane wrote:
> Simon Riggs <simon@2ndquadrant.com> writes:
>
>> On Fri, 2008-05-30 at 12:31 +0530, Gurjeet Singh wrote:
>>
>>> On Fri, May 30, 2008 at 10:40 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>>
>>>> But since you mention it: one of the plausible answers for fixing the
>>>> vacuum problem for read-only slaves is to have the slaves push an xmin
>>>> back upstream to the master to prevent premature vacuuming.
>>>>
>>> I think it would be best to not make the slave interfere with the
>>> master's operations; that's only going to increase the operational
>>> complexity of such a solution.
>>>
>
>
>> We ruled that out as the-only-solution a while back. It does have the
>> beauty of simplicity, so it may exist as an option or possibly the only
>> way, for 8.4.
>>
>
> Yeah. The point is that it's fairly clear that we could make that work.
> A solution that doesn't impact the master at all would be nicer, but
> it's not at all clear to me that one is possible, unless we abandon
> WAL-shipping as the base technology.
>
>
>
Quite. Before we start ruling things out let's know what we think we can
actually do.
I hope that NTT will release their code ASAP so we will have a better
idea of what we have and what we need.
cheers
andrew