On Fri, Oct 14, 2016 at 11:48 AM, Stephen Frost <sfrost@snowman.net> wrote:
* Magnus Hagander (magnus@hagander.net) wrote: > On Fri, Oct 14, 2016 at 4:35 AM, Stephen Frost <sfrost@snowman.net> wrote: > > * Peter Eisentraut (peter.eisentraut@2ndquadrant.com) wrote: > > > On 10/12/16 11:22 AM, Tom Lane wrote: > > > > The main problem we're trying to fix here is people thinking that > > > > something with "log" in the name contains discardable data. Just > > > > relocating the directory without renaming it won't improve that. > > > > > > I think it would help if we moved it to something like > > > "internal/pg_xlog" and "internal/pg_clog". Keep the name but move it > > > out of sight. > > > > I disagree that this will materially help with the issue. > > > > > We have a tool called pg_xlogdump in the standard installation. initdb > > > has an option --xlogdir, pg_basebackup has --xlog and others. Renaming > > > the xlog directory would make this all a bit confusing, unless we're > > > prepared to rename the programs and options as well. > > > > pg_xlogdump is not a user-facing tool, frankly, so I don't believe we > > should be terribly concerned about either leaving it named as-is or > > renaming it. I agree that we should consider adding alternative names > > to the options for initdb and pg_basebackup. > > Ugh. Changing the names of those options are probably going to break a > *lot* of things, a lot more than changing the names of the directories. Is > it really worth doing that? Especially if we are even more clear that > people should not be touching those directories in the first place.
I would point out that I said "adding alternative names", not "change/remove the existing options."
Oh, I missed that. Thanks for clarifying :)
That said, while I like the general idea of "make everything referring to transaction log/write-ahead xlog/xlog/wal/whatever refer in the same way", I'm not sure that it's a really pressing issue or that changing the name of the directory should drive those other changes.
Agreed.
> Those are just the tip of the iceberg. We do use the term xlog in a lot of > places (almost as many as wal, but that's a different problem)
True, and yes, we should consider the places that already talk about "wal", but, overall, I believe we can take this one step at a time and don't have to do everything all at once simply because we're changing the directory name. We're not changing what it *is*, after all.
Yeah, I think if we aim to fix everything at once, we'll get nothing done. That old saying of not letting perfection getting in the way of progress applies.
