Re: WIP: Failover Slots

On 24 February 2016 at 18:02, Craig Ringer <craig(at)2ndquadrant(dot)com> wrote:

> I really want to focus on the first patch, timeline following for logical
> slots. That part is much less invasive and is useful stand-alone. I'll move
> it to a separate CF entry and post it to a separate thread as I think it
> needs consideration independently of failover slots.
>

Just an update on the failover slots status: I've moved timeline following
for logical slots into its own patch set and CF entry and added a bunch of
tests.

https://commitfest.postgresql.org/9/488/

Some perl TAP test framework enhancements were needed for that; they're
mostly committed now with a few pending.

https://commitfest.postgresql.org/9/569/

Once some final changes are made to the tests for timeline following I'll
address the checkpoint issue in failover slots by doing the checkpoint of
slots at the start of a checkpoint/restartpoint, while we can still write
WAL. Per the comments in CheckPointReplicationSlots it's mostly done in a
checkpoint currently for convenience.

Then I'll write some TAP tests for failover slots and submit an updated
patch for them, by which time hopefully timeline following for logical
slots will be committed.

In other words this patch isn't dead, the foundations are just being
rebased out from under it.

--
Craig Ringer http://www.2ndQuadrant.com/
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