Stupid Oracle vktm tricks to improve VirtualBox performance
In the process of creating a demo VirtualBox image running OEL 6 and the Oracle database 11.2.0.3.0 I noticed the idle CPU consumption was quite high (8% on the guest, 35% on the host). The culprit turned out to be the Oracle database vktm process. This is a time keeping process - and it calls gettimeofday() *very* frequently. This can have a negative performance impact in virtualized environments. A colleague who is a database whiz suggested the following trick: sqlplus / as sysdba alter system set "_high_priority_processes"='LMS*' scope=spfile; This removes the vktm process from the list of high priority processes. After this change (you need to bounce the database) the idle CPU consumption comes down to 1-2% or so. A nice improvement! It goes without saying that this is: a) Totally unsupported b) Probably dangerous. This will most certainly break things in the database - such as statistics, auditing, etc. c) For demo/development use only. If y