On 2023-06-06 03:26, James Coleman wrote:
On Mon, Jun 5, 2023 at 4:30 AM torikoshia <torikos...@oss.nttdata.com>
wrote:
On 2023-06-03 02:51, James Coleman wrote:
> Hello,
>
> Thanks for working on this patch!
Sure thing! I'm *very interested* in seeing this available, and I
think it paves the way for some additional features later on...
> On Thu, Dec 8, 2022 at 12:10 AM torikoshia <torikos...@oss.nttdata.com>
...
> To put it positively: we believe that, for example, catalog accesses
> inside CHECK_FOR_INTERRUPTS() -- assuming that the CFI call is inside
> an existing valid transaction/query state, as it would be for this
> patch -- are safe. If there were problems, then those problems are
> likely bugs we already have in other CFI cases.
Thanks a lot for the discussion and sharing it!
I really appreciate it.
BTW I'm not sure whether all the CFI are called in valid transaction,
do you think we should check each of them?
I kicked off the regressions tests with a call to
ProcessLogQueryPlanInterrupt() in every single CHECK_FOR_INTERRUPTS()
call. Several hours and 52 GB of logs later I have confirmed that
(with the attached revision) at the very least the regression test
suite can't trigger any kind of failures regardless of when we trigger
this. The existing code in the patch for only running the explain when
there's an active query handling that.
Thanks for the testing!
I've attached v27. The important change here in 0001 is that it
guarantees the interrupt handler is re-entrant, since that was a bug
exposed by my testing. I've also included 0002 which is only meant for
testing (it attempts to log in the plan in every
CHECK_FOR_INTERRUPTS() call).
When SIGINT is sent during ProcessLogQueryPlanInterrupt(),
ProcessLogQueryPlanInterruptActive can remain true.
After that, pg_log_query_plan() does nothing but just returns.
AFAIU, v26 logs plan for each pg_log_query_plan() even when another
pg_log_query_plan() is running, but it doesn't cause errors or critical
problem.
Considering the problem solved and introduced by v27, I think v26 might
be fine.
How do you think?
Regards,
James
--
Regards,
--
Atsushi Torikoshi
NTT DATA CORPORATION
