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

Agreed.

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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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