Re: [HACKERS] PGXLOG variable worthwhile?

Jan Wieck wrote:
> "Nigel J. Andrews" wrote:
> > However, how is that going to work if tablespaces are introduced in 7.4. Surely
> > the same mechanism for tablespaces would be used for pg_xlog. As the tablespace
> > mechanism hasn't been determined yet, as far as I know, wouldn't it be best to
> > see what happens there before creating the TODO item for the log?
>
> No, tablespaces would have to be something DB specific, while the Xlog
> is instance wide (instance == one postmaster == installation == whatever
> you name that level).
>
> My vision is that we start off with two tablespaces per database,
> "default" and "default_idx", which are subdirectories inside the
> database directory. All (non-index-)objects created without explicitly
> saying what tablespace they belong to automatically belong to default.
> Indexes ... bla.
>
> The tablespace catalog will have a column telling the physical location
> of that directory. Moving it around will not be *that* easy, I guess,
> because the UPDATE of that entry has to go hand in hand with the move of
> all files in that damned directory. But that's another thing to sort out
> later, IMHO.

Yes, the nifty trick was to use a lstat() from pg_dump to learn if it is a
symlink and if so, where it points to.

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