Is CPU scaling available on the Stratus ftServer or NEC Express5800 running Red Hat Enterprise Linux 5.x?

Issue

CPU frequency scaling is not supported.

Environment

• Stratus ftServer 6300, 6310, 4500, or 2600 server
• NEC Express5800 R320a-E4, R320a-M4, R320b-M4, R320c-E4, or R320c-M4 server
• Red Hat Enterprise Linux 5.x

Resolution

Vendor's BIOS disables CPU frequency scaling and does not provide an option for the user to enable it. There are no plans from the vendor to allow or enable CPU frequency scaling in future.

Root Cause

Allowing CPU frequency scaling would interfere with the server's ability to keep its CPU pairs in lockstep, and would therefore compromise its fault-tolerant design.