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

On 19/07/10 20:58, Andres Freund wrote:
> On Monday 19 July 2010 19:57:13 Alvaro Herrera wrote:
>> Excerpts from Andres Freund's message of lun jul 19 11:58:06 -0400 2010:
>>> On Monday 19 July 2010 17:26:25 Hans van Kranenburg wrote:
>>>> When issuing an update statement in a transaction with ~30800 levels of
>>>> savepoint nesting, (which is insane, but possible), postgresql
>>>> segfaults due to a stack overflow in the AssignTransactionId function,
>>>> which recursively assign transaction ids to parent transactions.
>>>
>>> It seems easy enough to throw a check_stack_depth() in there - survives
>>> make check here.
>>
>> I wonder if it would work to deal with the problem non-recursively
>> instead.  We don't impose subxact depth restrictions elsewhere, why
>> start now?
> It looks trivial enough, but whats the point?

To support more than <insert abitrary limit here> subtransactions,
obviously.

--
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com