From: | Adrian Klaver <adrian(dot)klaver(at)aklaver(dot)com> |
---|---|
To: | Matthias Apitz <guru(at)unixarea(dot)de> |
Cc: | Postgres General <pgsql-general(at)postgresql(dot)org> |
Subject: | Re: Mysterious performance degradation in exceptional cases |
Date: | 2022-09-15 15:40:24 |
Message-ID: | c881d33c-4c96-f914-ca72-6bb5dcd36d89@aklaver.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-general |
On 9/14/22 22:33, Matthias Apitz wrote:
> El día miércoles, septiembre 14, 2022 a las 07:19:31a. m. -0700, Adrian Klaver escribió:
>
>> On 9/14/22 01:31, Matthias Apitz wrote:
>> Where is the inter library software, in your application or are you reaching
>> out to another application?
>
> The above 'app-server' fulfills the search requested by the
> 'ILL-software' (or the 'test search'), i.e. looks up for one single
> librarian record (one row in the PostgreSQL database) and delivers
> it to the 'ILL-software'. The request from the 'ILL-software' is not
> a heavy duty, more or less 50 requests per day.
>
>> Is the search running across a remote network?
>
> The real search comes over the network through a stunnel. But we
> watched with tcpdump the incoming search and the response by the
> 'app-server' locally. In the case of the timeout, the 'app-server' does not
> answer within 180 seconds, i.e. does not send anything into the stunnel,
> and the remote 'ILL-software' terminates the connection with an F-packet.
The 'app-server' does not answer, but does the database not answer also?
Have you looked to see if the database is providing a response in a
timely manner and if it is getting 'lost' in the 'app-server'?
Also have you considered Tom Lane's suggestion of using auto_explain?
>
> I will now:
>
> - shutdown the test search every 10 secs to see if the problem re-appears
> - set 'log_autovacuum_min_duration = 0' in postgresql.conf to see if
> the times of the problem matches;
>
> Thanks for your feedback in any case.
>
> matthias
>
--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com
From | Date | Subject | |
---|---|---|---|
Next Message | Adrian Klaver | 2022-09-15 15:59:48 | Re: get user info on log |
Previous Message | Ron | 2022-09-15 15:38:12 | Re: CVE-2022-2625 |