Comments on: Oracle Performance Issue: High Kernel-Mode CPU Usage http://www.pythian.com/news/1324/oracle-performance-issue-high-kernel-mode-cpu-usage/ News and views from Pythian DBAs Thu, 18 Mar 2010 16:45:18 +0000 http://wordpress.org/?v=2.8.4 hourly 1 By: Riyaj Shamsudeen http://www.pythian.com/news/1324/oracle-performance-issue-high-kernel-mode-cpu-usage/#comment-296747 Riyaj Shamsudeen Mon, 03 Nov 2008 17:22:00 +0000 http://www.pythian.com/blogs/1324/oracle-performance-issue-high-kernel-mode-cpu-usage#comment-296747 Hi Henry AMM is a 11g feature. In Linux, it is implemented using /dev/shm/. It is a very different implementation and so I don't know how that will interact with bigger SGA and NUMA architecture. Sorry, I have no ready access to Solaris + 11g+NUMA combination to test this out either. Thanks for reading our blog. Cheers Riyaj Hi Henry
AMM is a 11g feature. In Linux, it is implemented using /dev/shm/. It is a very different implementation and so I don’t know how that will interact with bigger SGA and NUMA architecture.

Sorry, I have no ready access to Solaris + 11g+NUMA combination to test this out either.

Thanks for reading our blog.

Cheers
Riyaj

]]> By: Henry Poras http://www.pythian.com/news/1324/oracle-performance-issue-high-kernel-mode-cpu-usage/#comment-296731 Henry Poras Mon, 03 Nov 2008 16:28:24 +0000 http://www.pythian.com/blogs/1324/oracle-performance-issue-high-kernel-mode-cpu-usage#comment-296731 Is the shared memory issue still a problem if you are using Automatic Memory Management? I believe the OS then uses /dev/shm to manage memory, not large (multiple) shared memory segments. (see Tanel Poder's blog http://tinyurl.com/4eqjrb). Is the shared memory issue still a problem if you are using Automatic Memory Management? I believe the OS then uses /dev/shm to manage memory, not large (multiple) shared memory segments. (see Tanel Poder’s blog http://tinyurl.com/4eqjrb).

]]>