Re: Two Phase Commit WAS: Re: Two weeks to feature freeze

I second the agreement ... a 'reference implementation', of sorts, at
least gives someone to build on then starting right from scratch ...



On Mon, 23 Jun 2003, Bruce Momjian wrote:

>
> Agreed.
>
> ---------------------------------------------------------------------------
>
> Josh Berkus wrote:
> > Tom,
> >
> > > No.  I want to know what the subordinate does when it's promised to
> > > commit and the co-ordinator never responds.  AFAICS the subordinate
> > > is screwed --- it can't commit, and it can't abort, and it can't expect
> > > to make progress indefinitely on other work while it's holding locks
> > > for the not-quite-committed transaction.
> >
> > AFAIK, MS SQL Server's two-phase commit works like this ... if both servers
> > prepare, and one crashes, the transaction is screwed up.  Somewhat unreliable
> > considering the frequence with which MSSQL crashes, yet it seems to be good
> > enough for several companies to sell "solutions" based on it. (performance is
> > also appalling, but that's a different issue)
> >
> > Anybody have a grasp of Oracle internals for 2PC?
> >
> > Anyway, I would vote for a first implemenation for 2PC which addressed the
> > commit-then-crash issue in some expedient-but-not-reliable way, and putting
> > 2PC in /contrib with a "not for production use" warning.  Some people will
> > use it in production anyway, and hopefully one or more of them will put in
> > the dozens of hours required to make it reliable.
> >
> > --
> > Josh Berkus
> > Aglio Database Solutions
> > San Francisco
> >
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>
> --
>   Bruce Momjian                        |  http://candle.pha.pa.us
>   pgman@candle.pha.pa.us               |  (610) 359-1001
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Marc G. Fournier                   ICQ#7615664               IRC Nick: Scrappy
Systems Administrator @ hub.org
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