Re: RFC: Logging plan of the running query

torikoshia <torikoshia@oss.nttdata.com>

From: torikoshia <torikoshia@oss.nttdata.com>

To: Fujii Masao <masao.fujii@oss.nttdata.com>, pgsql-hackers@lists.postgresql.org

Date: 2022-05-16T08:02:40Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

ecpg: Catch zero-length Unicode identifiers correctly
- a18b6d2dc288 15.0 cited
Improve warning message in pg_signal_backend()
- 7fa945b857cc 15.0 cited
Add assert to ensure that page locks don't participate in deadlock cycle.
- 72e78d831ab5 13.0 cited

Attachments

v22-0001-log-running-query-plan.patch (text/x-diff) patch v22-0001

On 2022-03-09 19:04, torikoshia wrote:
> On 2022-02-08 01:13, Fujii Masao wrote:
>> AbortSubTransaction() should reset ActiveQueryDesc to
>> save_ActiveQueryDesc that ExecutorRun() set, instead of NULL?
>> Otherwise ActiveQueryDesc of top-level statement will be unavailable
>> after subtransaction is aborted in the nested statements.
> 
> I once agreed above suggestion and made v20 patch making
> save_ActiveQueryDesc a global variable, but it caused segfault when
> calling pg_log_query_plan() after FreeQueryDesc().
> 
> OTOH, doing some kind of reset of ActiveQueryDesc seems necessary
> since it also caused segfault when running pg_log_query_plan() during
> installcheck.
> 
> There may be a better way, but resetting ActiveQueryDesc to NULL seems
> safe and simple.
> Of course it makes pg_log_query_plan() useless after a subtransaction
> is aborted.
> However, if it does not often happen that people want to know the
> running query's plan whose subtransaction is aborted, resetting
> ActiveQueryDesc to NULL would be acceptable.
> 
> Attached is a patch that sets ActiveQueryDesc to NULL when a
> subtransaction is aborted.
> 
> How do you think?

Attached new patch to fix patch apply failures.

-- 
Regards,

--
Atsushi Torikoshi
NTT DATA CORPORATION