Re: Subtransaction commits and Hot Standby

On Sun, 2008-10-05 at 14:51 -0400, Alvaro Herrera wrote:
> Simon Riggs wrote:
> 
> > OK, spent long time testing various batching scenarios for this using a
> > custom test harness to simulate various spreads of xids in transaction
> > trees. All looks fine now.
> 
> I had a look and was mostly rephrasing some comments and the README
> (hopefully I didn't make any of them worse than they were), when I
> noticed that the code to iterate thru pages could be refactored.  I
> think the change makes the algorithm in TransactionIdSetTreeStatus
> easier to follow.

OK, thanks for the review.

> I also noticed that TransactionIdSetPageStatus has a "subcommit" arg
> which is unexplained.  I sort-of understand the point, but I think it's
> better that you fill in the explanation in the header comment (marked
> with XXX)

I'll explain some more in the code, and in the README with worked
examples of what we need to do and why.

> I hope I didn't break the code with the new function
> set_tree_status_by_pages -- please recheck that part.

Eyeballs OK.

> I didn't test this beyond regression tests.

-- Simon Riggs           www.2ndQuadrant.comPostgreSQL Training, Services and Support