On 2021-10-15 15:17, torikoshia wrote:
> I only took a quick look at pg_query_state, I have some questions.
>
> pg_query_state seems using shm_mq to expose the plan information, but
> there was a discussion that this kind of architecture would be tricky
> to do properly [1].
> Does pg_query_state handle difficulties listed on the discussion?
Sorry, I forgot to add the URL.
[1]
https://www.postgresql.org/message-id/9a50371e15e741e295accabc72a41df1%40oss.nttdata.com
> It seems the caller of the pg_query_state() has to wait until the
> target process pushes the plan information into shared memory, can it
> lead to deadlock situations?
> I came up with this question because when trying to make a view for
> memory contexts of other backends, we encountered deadlock situations.
> After all, we gave up view design and adopted sending signal and
> logging.
Discussion at the following URL.
https://www.postgresql.org/message-id/9a50371e15e741e295accabc72a41df1%40oss.nttdata.com
Regards,
--
Atsushi Torikoshi
NTT DATA CORPORATION
