Re: serverless postgresql - Mailing list pgsql-general

From Christopher Browne
Subject Re: serverless postgresql
Date
Msg-id m38ykbdsfm.fsf@wolfe.cbbrowne.com
Whole thread Raw
In response to serverless postgresql  (Jeff Bowden <jlb@houseofdistraction.com>)
Responses Re: serverless postgresql
List pgsql-general
jlb@houseofdistraction.com (Jeff Bowden) wrote:
> Tom Lane wrote:
>>Not only are the developers uninterested in it, the developers actively
>>oppose it.  We think an embedded database library cannot be reliable
>>enough to meet our notion of a "database", since it would be subject to
>>failures anytime the surrounding application has a bug.  Keeping the
>>client code in a separate process is a far more robust design.

> That makes sense to me.  I wonder if sqlite suffers for this problem
> (e.g. app crashing and corrupting the database).

I'm not sure its use has yet been so widespread that there is a good
feel for this.  It is doubtless _possible_; "crash patterns" likely
_don't_ lead to enormous disasters when databases are small,
localized, and the apps probably _don't_ crash all the time.

> What about the notion of running postmaster on-demand as the user?
> Is that something that anyone has experience with?  It seems like it
> would solve the complex configuration problems without compromising
> robustness or requiring any special support other than sufficient
> command-line parameters.

I haven't had call for this being controlled "by the application," but
I can't see it being vastly troublesome.  And I _don't_ see it
requiring lots of "command line" parameters; you just need to specify
the directory where the configuration is.

> Oh yeah, that brings me to another question.  I was looking at the
> postmaster command-line switches and I couldn't find any that would
> allow me to point it at an arbitrary config file but then I had a
> look around and it seems that the .conf files are already used by
> the various startup scripts.  Does postmaster itself ever read the
> .conf files or is it controlled strictly by switches?

All of the .conf files are in one directory, and that directory is
controlled by either the value of environment variable PGDATA or the
"-D" command parameter.

It seems not-overly-valuable to have the .conf files be able to be
specified in random other locations.

Is there some particular reason you have in mind why you would want to
_ignore_ the configuration in $HOME/DBDIR and instead use
configuration in some other random location?  I would think that
collecting the config into one directory, as is done right now, is a
_good_ thing.
--
let name="cbbrowne" and tld="ntlug.org" in name ^ "@" ^ tld;;
http://www3.sympatico.ca/cbbrowne/lsf.html
"Even in the  area of anticompetitive conduct, Microsoft  is mainly an
imitator." -- Ralph Nader (1998/11/11)

pgsql-general by date:

Previous
From: Christopher Browne
Date:
Subject: Re: what we need to use postgresql in the enterprise
Next
From: "Nigel J. Andrews"
Date:
Subject: Re: sequence incrementing twice