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

On Mon, Jul 19, 2010 at 4:35 PM, Andres Freund <andres@anarazel.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.

--
Robert Haas
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