ITM, Oracle, Java and Linux huge pages
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Newer Linux kernels can allocate memory pages of 2Mb in size transparently, without code changes in the applications.
Oracle recommends to disable THP feature if the Linux machine is used as Oracle DB server, and that hugepages be used only by Oracle engine.
ITM components do not request allocation of huge pages, but the embedded JRE component can request allocation of 2M memory pages and potentially cause issues with the Oracle DB, especially at machine startup where the JRE is used to start ITM agents.
Java executable parameter -Xlp can be used to force the page size, a full explanation is available here:
To configure page memory allocation in ITM JRE environment, edit file [ITM
then modify this last line as follows and save it:
Now the ITM java is be forced to use 4k pages and does not interfere with Oracle.