Re: Fast index build vs. PITR

Tom Lane wrote:
> Greg Stark <gsstark(at)mit(dot)edu> writes:
> > I'm not clear that building from WAL is really going to be that much faster.
> > A) algorithmically it's only the factor of log(n) that you're talking about.
> > and B) the WAL will have records for every write, not just the final product,
> > so it might potentially have a lot more writes to do.
>
> Wrong ... what we log in WAL for a btree index build is just the series
> of completed index page images. Recreation of the index would proceed
> at whatever your disk read/write bandwidth is.
>
> Like Alvaro, I suspect that people who are using PITR will be concerned
> about recovery time, and would not be thrilled with any scenario that
> involves REINDEX to get the system back on its feet.

Agreed.

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