Re: BUG #5566: High levels of savepoint nesting trigger stack overflow in AssignTransactionId

On Thu, Jul 22, 2010 at 5:01 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> On Mon, Jul 19, 2010 at 4:35 PM, Andres Freund <andres(at)anarazel(dot)de> wrote:
>>> Well. I got that far. But why is that something worthy of support?
>>> For one I have a hard time imaging a sensible use case, for another doing
>>> anything in that deeply nested transactions seems to gets really slow (the
>>> chain of transactions gets walked at some places for one thing, there seem
>>> to be others).
>>>
>>> If want I can write a patch for that as well, seems to be trivial enough.
>> Updated patch attached.
>
> Considering that this is a crasher, I think we'll need to back-patch
> this.  The proposed patch applies only as far back as 8.3, due to the
> lazy XID assignment changes in that version, but it looks like the bug
> exists all the way back to 8.0.  It looks like only minor adjustments
> are required for the older branches, though.  7.4 is not affected, as
> it does not have subtransactions.

Can someone provide a reproducible test case for this bug? I wasn't
easily able to reproduce it.

Attached please find a cleaned-up version of the patch for CVS HEAD.
I am having a bit of trouble compiling the 8.2 patch I hacked up, and
I believe that's because the git respository is borked.

--
Robert Haas
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