Re: pg_xlogdump --stats

At 2014-08-21 10:06:39 +0300, hlinnakangas(at)vmware(dot)com wrote:
>
> Committed the patch to add INT64_MODIFIER, with minor fixes.

Thank you.

> The new rm_identify method needs to be documented. […]
> Perhaps add comments to the RmgrData struct, explaining
> all of the methods.

OK, I'll submit a patch to add these comments.

> I think the names that rm_identify returns should match those that the
> rm_desc functions print.

I had originally started off trying to keep the output in sync, but it
doesn't work very well. There are rm_desc functions that print things
like "truncate before" and "Create posting tree", and many decisions
are quite arbitrary ("freeze_page", "cleanup info", "multi-insert").

I think it's better the (grep-friendly) way it is. If anything, perhaps
rm_desc should output "${rm_identify}[: optional explanation]". That
would also make it very clear what should go in rm_identify and what
should go in rm_desc.

Thoughts?

> The corresponding rm_identify output is:
>
> HOT_UPDATE+INIT

The +INIT is admittedly a special case, and I would have no objection to
writing that as (INIT) or something instead.

-- Abhijit