On Tue, Feb 10, 2009 at 8:53 AM, Alvaro Herrera <alvhe...@commandprompt.com> wrote: > I'm not sure that this calls for a change in autovacuum itself; it seems > to be that whatwe really need is the ability to change postgresql.conf > settings from the SQL interface. This has been discussed at length > elsewhere, and I think we need to bite the bullet eventually.
I'd like to take a crack at identifying the bullet that needs to be bitten here: comments. People like to use comments to document old settings that they may once have had, and why they changed them, and we also ship comments that document the meaning of many of our settings. IIRC, much of the last round of this discussion centered on where new settings would be inserted into the file (which might involve trying to identify the commented-out version of that setting), whether to comment out the old line for a particular setting and insert a new line (or just replace the old line), what to do about comments on the same line as the GUC, etc. Any solution that we attempt to engineer this problem is unlikely to be able to pass the Turing test, and so it's likely to get some cases "wrong", as judged by the human intelligence of the person who wrote the comment that got masticated. If we resign ourselves to the fact that this will not work very well unless our postgresql.conf file is intended to be read and written primarily by machines, and only secondarily by humans when necessary to recover from a bad situation, we can make some progress. ...Robert -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers