Re: pg_xlog -> pg_xjournal? - Mailing list pgsql-hackers

From David Steele
Subject Re: pg_xlog -> pg_xjournal?
Date
Msg-id 556E26EA.2000406@pgmasters.net
Whole thread Raw
In response to Re: pg_xlog -> pg_xjournal?  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: pg_xlog -> pg_xjournal?  (Jim Nasby <Jim.Nasby@BlueTreble.com>)
List pgsql-hackers
On 5/31/15 1:46 PM, Tom Lane wrote:
> Hm.  I think the impact on third-party backup tools would be rather bad,
> but there's a simple modification of the idea that might fix that:
> just always create pg_xlog as a symlink to pg_xjournal during initdb.
> Anybody who blindly removes pg_xlog won't have done anything
> irreversible.  We could deprecate pg_xlog and stop creating the symlink
> after a few releases, once third-party tools have had a reasonable
> amount of time to adjust.

As the author of a third-party backup tool I'd prefer to make a clean
break and just rename the directories in a single release.  9.5 has
similar backup/restore related changes with no nod to backwards
compatibility.

And that's fine.  Applications can iterate faster than databases and
they should.

Two options to make lives easier:

1) An initdb option to create the necessary symlinks as Tom suggests,
just not by default.
2) Instructions in the release notes for users who did not see the
initdb option in the first place.

--
- David Steele
david@pgmasters.net


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