Q-Logic IB6054601-00 D Manuel D’Utilisation

2 – InfiniPath Cluster Administration
Configuration and Startup

2-4

IB6054601-00 D

Q

This breaks down to a memory footprint of 331MB per node, as follows:

A properly configured BIOS is required. The BIOS settings, which are stored in 
non-volatile memory, contain certain parameters characterizing the system,. These 
parameters may include date and time, configuration settings, and information about 
the installed hardware. 

There are currently two issues concerning BIOS settings that you need to be aware 
of:

■

ACPI needs to be enabled

■

MTRR mapping needs  to be set to “Discrete”

MTRR (Memory Type Range Registers) is used by the InfiniPath driver to enable 
write combining to the InfiniPath on-chip transmit buffers. This improves write 
bandwidth to the InfiniPath chip by writing multiple words in a single bus transaction 
(typically 64). This applies only to x86_64 systems.

However, some BIOSes don’t have the MTRR mapping option. It may be referred 
to in a different way, dependent upon chipset, vendor, BIOS, or other factors. For 
example, it is sometimes referred to as "32 bit memory hole", which should be 
enabled. 

If there is no setting for MTRR mapping or 32 bit memory hole, please contact your 
system or motherboard vendor and inquire as to how write combining may be 
enabled. 

ACPI and MTRR mapping issues are discussed in greater detail in the 
Troubleshooting section of the InfiniPath User Guide.

BIOS settings on IBM Blade Center H (Power) systems do not need 
adjustment.

Driver

9

Per node

MPI

316 

4*71 MB (MPI per process) 
+ 32 MB (shared memory 
per node)

OpenFabrics

6

6 MB + 200 KB per node