Re: Speedup twophase transactions

Thanks Michael,

I was away for a bit. I will take a look at this patch and get back to you
soon.

Regards,
Nikhils

On 22 March 2017 at 07:40, Michael Paquier <michael(dot)paquier(at)gmail(dot)com>
wrote:

> On Fri, Mar 17, 2017 at 5:15 PM, Michael Paquier
> <michael(dot)paquier(at)gmail(dot)com> wrote:
> > On Fri, Mar 17, 2017 at 5:00 PM, Nikhil Sontakke
> > <nikhils(at)2ndquadrant(dot)com> wrote:
> >> Micheal, it looks like you are working on a final version of this
> patch? I
> >> will wait to review it from my end, then.
> >
> > I have to admit that I am beginning to get drawn into it...
>
> And here is what I got. I have found a couple of inconsistencies in
> the patch, roughly:
> - During recovery entries marked with ondisk = true should have their
> start and end LSN reset to InvalidXLogRecPtr. This was actually
> leading to some inconsistencies in MarkAsPreparing() for 2PC
> transactions staying around for more than 2 checkpoints.
> - RecoverPreparedTransactions(), StandbyRecoverPreparedTransactions()
> and PrescanPreparedTransactions() doing both a scan of pg_twophase and
> the shared memory entries was way too complicated. I have changed
> things so as only memory entries are scanned by those routines, but an
> initial scan of pg_twophase is done before recovery.
> - Some inconsistencies in the comments and some typos found on the way.
> - Simplification of some routines used in redo, as well as simplified
> the set of routines made available to users.
>
> Tests are passing for me, an extra lookup would be nice.
> --
> Michael
>

--
Nikhil Sontakke http://www.2ndQuadrant.com/
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