Re: Server instrumentation patch - Mailing list pgsql-hackers

Dave Page wrote:
> > The current version of the patch only moves those functions he wants. 
> > Marc says he wants them all moved, and I agree.
> 
> OK - did you see Andreas' response to why he hadn't done that (it was
> actually posted in response to your original query, not Marcs)? In a
> nutshell, the functions that had not been moved returned values that
> were easily derived from the other functions, and thus could be
> considered bloat?
> 
> The functions included in the patch were:
> 
> int8 pg_tablespace_size(oid)    - Return the size of the tablespace in
> bytes
> int8 pg_database_size(oid)    - Return the size of the database in
> bytes
> int8 pg_relation_size(oid)    - Return the size of the relation in
> bytes
> text pg_size_pretty(int8)    - Pretty-print the byte value
> 
> The ones left out were:
> 
> int8 database_size(name)    - Return the size of the database in
> bytes (by name)
> int8 relation_size(text)    - Return the size of the relation in
> bytes (by name)
> int8 indexes_size(text)       - Return the size of the indexes on the
> named relation
> int8 total_relation_size(text) - Return relation_size(text) +
> indexes_size(text) + relation_size(text->toast tables)
> setof record relation_size_components(text) - return a pretty-print set
> of values from above.
> 
> I don't feel particularly strongly either way, but given the normal
> desire not to bloat the backend necessarily, I have to question the need
> to include the latter functions.

OK, well, let's talk about what we want done, then someone can work up a
patch.  Does someone want to make a proposal here on what to do?

> > Well, from the May, 2005 discussion URL you posted, I see a 
> > clear reply
> > to the idea of adding the I/O functions to the backend:
> > 
> >     
> > http://archives.postgresql.org/pgsql-hackers/2005-05/msg00874.php
> > 
> > Now, you can agree or disagree that there are issues with the I/O
> > functions, but the concern was raised in May, and not 
> > addressed at all,
> > either via email or the patch.
> 
> Maybe that's the wrong URL, but all I see there is a vague recollection
> from Tom that there were security issues. In the next message, Andreas
> recalls how you and he worked out the issues that were raised - I
> believe this is the thread
> http://archives.postgresql.org/pgsql-hackers/2004-07/msg00793.php.
> Mhonarc has made a mess of the thread so it does seem to break in a few
> places, and it is possible I've missed part.

The security issue is that we didn't want the backend to be able to
read/write outside of /pgdata, and I think we have that working, except
that I have no idea how it will handle config files outside /pgdata. 
Maybe that was in the patch --- I don't know.

I think we need to see a new patch with just the i/o functions so we can
review it.  I personally think the I/O functions are a good idea, but I
need to be considerate of others in the community who have concerns.

> > For the second, please supply a patch that moves _all_ of dbsize into
> > the main server.  I think we have agreement on that.
> 
> If that remains the case having seen my comments above echoing Andreas'
> concerns then sure, if that's what it takes to get them in, so be it.
> Please confirm either way.

Let's discuss what to move/delete/keep in contrib.

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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