HP ProLiant BL490c Configuring the HP ProLiant Server BIOS for Low-Latency App - Page 7

BIOS low-latency settings To configure BIOS for minimum latency, you can disable Processor Power and Utilization Monitoring, Memory Pre-Failure Notification, or both. Disabling each option causes some server features to become unavailable. Before reconfiguring BIOS, be sure that none of the features described below are required. Disabling Processor Power and Utilization Monitoring disables the following features: • iLO 2 Processor State Monitoring • Insight Power Manager CPU Utilization Reporting • HP Dynamic Power-Savings Mode Disabling Memory Pre-Failure Notification has the following effects: • Disables Memory Pre-Failure Warranty Support • Disables notification when correctable memory errors occur above a pre-defined threshold • Forces the system to run in Advanced ECC Mode, regardless of the mode configured in RBSU IMPORTANT: Online Spare Mode, Mirroring Mode, and Lock-step Mode are not supported when Memory Pre-Failure Notification support is disabled. Supported AMP modes depend on the generation and model of the ProLiant server. Disabling Processor Power and Utilization Monitoring provides the greatest benefit in low-latency environments. Disabling Memory Pre-Failure Notification has a much smaller effect because this feature generates an interrupt at a very low frequency - from once every several minutes to as seldom as once an hour on HP ProLiant G6 servers and server blades with Intel® Xeon® processors. Because of the very low frequency of this SMI, only the most latency-sensitive environments should have Memory Pre-Failure Notification disabled. Some low-latency kernels provide features that result in system latency greater than that caused by Memory Pre-Failure Notification. For example, Red Hat Enterprise Linux 5 kernel soft lockup detection may generate an interrupt that results in an approximately 1-second latency each time it occurs. This latency is greater than that caused by Memory Pre-Failure Notification. In any case, disabling Memory Pre-Failure Notification does not disable the Advanced ECC mode or correction of errors. Uncorrectable errors are still flagged, logged, and bring the system down. The only difference when this SMI is disabled is that there is no early notification if the uncorrectable error threshold is exceeded. Upgrading BIOS Before attempting to disable Processor Power and Utilization Monitoring or Memory Pre-Failure notification, upgrade the BIOS to the most recent version. IMPORTANT: Before upgrading the BIOS in HP ProLiant G1 through G5 server blades with InfiniBand mezzanine cards installed, upgrade the InfiniBand mezzanine card firmware. To obtain the mezzanine card firmware: 1. Search the HP website (http://www.hp.com/go/bladesystem) for the mezzanine card part number. 2. Select the installed OS. 3. Download the upgrade. Configuring BIOS 7