Yes, am also thoght that something similar could have happening; the main
app is connected to a PLC and interacting with a robot, that answer would
make sense.
I'll check with the developers of the app.
Thanks
David Ramírez Reyes
Profesión: Padre de Familia y DBA en mis ratos libres
Profession: Parent and DBA in my spare time
On 1 August 2016 at 12:24, Woody McKay <woody.mckay@xxxxxxxxx> wrote:
I've know some old apps that issues "select 'x' from dual" every time they
wanted to use the connection (in a connection pool) to ensure that the
connection was hot and alive. In performance testing, this select was
executed so much that it showed up in top 10 and consumed considerable
resources. I talked with the Java architect and that was their solution to
test the connection before using it... I couldn't get them to eliminate
it, but was able to get them to not do it every single time... maybe every
100...
On Mon, Aug 1, 2016 at 1:18 PM, David Ramírez Reyes <dramirezr@xxxxxxxxx>
wrote:
Hello all,
Windows Server 2012 STD (physical server), Oracle DB 11g R2 Std.
Since 4 days ago, there are some cpu pick problems on the server (1 cpu 3
cores, 32 GB in RAM); they have been happening 2 or 3 times during the day
and take around 2-5 mins (the cpu picks to 100%, 99 of it used by the
Oracle Service).
I checked the threads running on it with Process Explorer, but there's no
specific query consuming it, but many consuming less than 5% of cpu; when
looking at the DB to find out the SQL text, I found that the query is
select 'x' from dual
AWR is disabled and no OEM console is configured (the DB was installed by
a vendor for Engineering team, I don't have so much information about this
specific setup).
Have you ever have had problems with " select 'x' from dual" query?,
tried to google some but haven't found something similar.
Thanks in advance.
Regards
David Ramírez Reyes
Profesión: Padre de Familia y DBA en mis ratos libres
Profession: Parent and DBA in my spare time
--
Sincerely,
WoodyMcKay
