Re: HOT - whats next ?

Simon Riggs wrote:
> On Fri, 2007-03-02 at 10:08 -0500, Tom Lane wrote:
> 
> > How much testing of this patch's concurrent behavior has been done?
> > I'm wondering if any other locking thinkos are in there ...
> 
> This version of HOT is being developed from scratch, with as much
> feedback from the community as possible. The idea was to build it up
> brick by brick, so that each assumption/decision could be challenged as
> we go. The idea was to avoid a huge review at the end, which could lead
> to a fatal flaw being discovered too late to make the release.

Yes, as Joshua Drake said, HOT is a model of how to develop complex
patches in the community.

> The right kind of testing is clearly going to be important to getting
> HOT right. Back in July, we spent some time building concurrent psql
> specifically to allow test cases to be written that referenced multiple
> sessions. Even if we don't like that thought for production, it would be
> great to be able to have a tool that allowed multi-session test cases to
> be written. Experience was that it was much, much easier to get a test
> case written in a single script where you could easily read the
> statement history.

Yes, I am assuming we are getting the concurrent psql patch in 8.3.  It
was stalled because we were waiting for regression tests and use
illustrations.

> 
> It would also be very useful to have a version of pgstattuple that
> worked with heaps, so test cases can be written that examine the header
> fields, info flags etc. It would be useful to be able to specify the
> basic behaviour in terms of explicit test cases.
> 
> Would those two approaches to test execution be desirable in the
> regression tests?

Sure.

--  Bruce Momjian  <bruce@momjian.us>          http://momjian.us EnterpriseDB
http://www.enterprisedb.com
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