Re: Replication identifiers, take 4

On 17 April 2015 at 18:12, Heikki Linnakangas <hlinnaka(at)iki(dot)fi> wrote:

> On 04/17/2015 12:04 PM, Simon Riggs wrote:
>
>> On 17 April 2015 at 09:54, Andres Freund <andres(at)anarazel(dot)de> wrote:
>>
>> Hrmpf. Says the person that used a lot of padding, without much
>>> discussion, for the WAL level infrastructure making pg_rewind more
>>> maintainable.
>>>
>>
>> Sounds bad. What padding are we talking about?
>>
>
> In the new WAL format, the data chunks are stored unaligned, without
> padding, to save space. The new format is quite different to the old one,
> so it's not straightforward to compare how much that saved.

The key point here is the whole WAL format was changed to accommodate a
minor requirement for one utility. Please notice that nobody tried to stop
you doing that.

The changes Andres is requesting have a very significant effect on a major
new facility. Perhaps there is concern that it is an external utility?

If we can trust Heikki to include code into core that was written
externally then I think we can do the same for Andres.

I think its time to stop the padding discussion and commit something
useful. We need this.

--
Simon Riggs http://www.2ndQuadrant.com/
<http://www.2ndquadrant.com/>
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