Re: SSI and 2PC

"Kevin Grittner" <Kevin.Grittner@wicourts.gov> wrote: 
> "Kevin Grittner" <Kevin.Grittner@wicourts.gov> wrote:
>  
>> In going back through old emails to see what issues might have
>> been raised but not yet addressed for the SSI patch, I found the
>> subject issue described in a review by Jeff Davis here:
>>  
>> http://archives.postgresql.org/pgsql-hackers/2010-10/msg01159.php
>  
> After reviewing the docs and testing things, I'm convinced that
> more work is needed.  Because the transaction's writes aren't
> visible until COMMIT PREPARED is run, and write-write conflicts
> are still causing serialization failures after PREPARE
> TRANSACTION, some of the work being done for SSI on PREPARE
> TRANSACTION needs to be moved to COMMIT PREPARED.
I'm now also convinced that Jeff is right in his assessment that
when a transaction is prepared, information about predicate locks
and conflicts with other prepared transactions must be persisted
somewhere.  (Jeff referred to a "2PC state file".)
I'm trying not to panic here, but I haven't looked at 2PC before
yesterday and am just dipping into the code to support it, and time
is short.  Can anyone give me a pointer to anything I should read
before I dig through the 2PC code, which might accelerate this?
-Kevin