Power saving mode on Dells and poor database performance
Date: Fri, 11 Dec 2015 10:17:20 +0000
Message-ID: <CAOHpfbEOQBwDRjiquOdw-6fJAgnQqC6YwQ8sr5wexjXOAjHXoQ_at_mail.gmail.com>
OK, this is embarrassing. (For Dell or Intel?)
We've just identified that BIOS settings on our Dell PowerEdge R730 had not been set as we thought and were actually set to "Performance per watt" mode. Turns out this backs off CPU to 1GHz from 3.3GHz and even shuts cores down.
Setting this to Performance mode has dramatically improved the run time of some big batch processes, and brought average CPU utilisation down from around 40-50% to 10-15%. The CPUs were essentially going to sleep while inactive.
A VMWare tool was involved. It had been used to propagate the BIOS settings. Apparently the Dells accepted the settings, appeared to be set to Performance mode but due to a BIOS bug were still implementing Power Saving. Some of our processes now run in half the time they did yesterday.
Regards,
J
-- http://www.freelists.org/webpage/oracle-lReceived on Fri Dec 11 2015 - 11:17:20 CET