Re: huge CPU load after UEK upgrade

Looks like another ACPI bug. Can you try booting the servers with NOACPI option?

On 8/12/21 2:40 AM, Laurentiu Oprea wrote:
> Hello everyone,
>
> I know this is more of a linux question but maybe someone had a
> similar issue.
>
> I started to upgrade the kernel version from UEK3 to UEK4 on servers
> (rac 2/3 nodes) running OL6. I had no issue upgrading the kernel on
> virtual machines.
>
> When I upgraded the first rac node located on physical hardware, after
> starting the oracle instances the cpu load went crazy, the whole
> system was far slower. For example the cpu load on the other rac nodes
> with UEK3 was 4/3/3/ while the upgraded node load was 107/104/77 with
> only half the instances started, this workload being created even if
> the instances had no significant workload (they were just started)
>
> I observed that with the new kernel version when oracle
> instances start there is quite a big number of kworker processes. Perf
> top will show me as overhead
> 17.24% [kernel]  _raw_spin_lock
> 4.50% [kernel] acpi_os_write_port
>
> Does anyone have any idea on what could be the issue?
>
> THanks a lot.

-- 
Mladen Gogala
Database Consultant
Tel: (347) 321-1217
https://dbwhisperer.wordpress.com

--
http://www.freelists.org/webpage/oracle-l