Re: Keepalive for max_standby_delay

On Wed, Jun 2, 2010 at 2:03 PM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> On Wed, 2010-06-02 at 13:45 -0400, Tom Lane wrote:
>> Stephen Frost <sfrost(at)snowman(dot)net> writes:
>> > * Tom Lane (tgl(at)sss(dot)pgh(dot)pa(dot)us) wrote:
>> >> Comments?
>>
>> > I'm not really a huge fan of adding another GUC, to be honest.  I'm more
>> > inclined to say we treat 'max_archive_delay' as '0', and turn
>> > max_streaming_delay into what you've described.  If we fall back so far
>> > that we have to go back to reading WALs, then we need to hurry up and
>> > catch-up and damn the torpedos.
>>
>> If I thought that 0 were a generally acceptable value, I'd still be
>> pushing the "simplify it to a boolean" agenda ;-).  The problem is that
>> that will sometimes kill standby queries even when they are quite short
>> and doing nothing objectionable.
>
> OK, now I understand. I was just thinking the same as Stephen, but now I
> agree we need a second parameter.

I too was thinking the same as Stephen, but now I also agree we need a
second parameter. I think the whole design Tom proposed seems good.

--
Robert Haas
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