On Wed, Sep 9, 2015 at 6:03 AM, Greg Stark <stark@mit.edu> wrote:
On Sun, Sep 6, 2015 at 1:25 PM, Andres Freund <andres@anarazel.de> wrote: > My vote is that we should try to get freeze maps into 9.6 - that seems > more realistic given that we have a patch right now. Yes, it might end > up being superflous churn, but it's rather localized. I think around > we've put off significant incremental improvements off with the promise > of more radical stuff too often.
Superfluous churn in the code isn't too bad. But superfluous churn in data formats might be a bit more scary. Would we be able to handle pg_upgrade from a database with or without a freezemap? Would you have to upgrade once to add the freezemap then again to remove it?
Surely we wouldn't introduce and remove freeze-maps between minor versions. So either it is a new major version, in which case you would be doing the upgrade anyway, or they would be added and then removed again all within one development cycle; and running unreleased code always has on-disk incompatibility churn. Or am I missing your point here?
