What does "please specify mtrr_gran_size/mtrr_chunk_size" mean in the boot messages

Solution In Progress - Updated -

Issue

  • Seeing the following in boot messages:
Dec 21 10:19:49 server kernel: gran_size: 256M      chunk_size: 512G        num_reg: 8      lose cover RAM: 1G
Dec 21 10:19:49 server kernel: gran_size: 256M      chunk_size: 1024G       num_reg: 8      lose cover RAM: 1G
Dec 21 10:19:49 server kernel: gran_size: 256M      chunk_size: 2048G       num_reg: 8      lose cover RAM: 1G
Dec 21 10:19:49 server kernel: gran_size: 512M      chunk_size: 512M        num_reg: 8      lose cover RAM: 1G
Dec 21 10:19:49 server kernel: gran_size: 512M      chunk_size: 1G  num_reg: 8      lose cover RAM: 1G
Dec 21 10:19:49 server kernel: gran_size: 512M      chunk_size: 2G  num_reg: 8      lose cover RAM: 1G
Dec 21 10:19:49 server kernel: gran_size: 512M      chunk_size: 4G  num_reg: 8      lose cover RAM: 1G
Dec 21 10:19:49 server kernel: mtrr_cleanup: can not find optimal value
Dec 21 10:19:49 server kernel: please specify mtrr_gran_size/mtrr_chunk_size

Environment

  • Red Hat Enterprise 6

Subscriber exclusive content

A Red Hat subscription provides unlimited access to our knowledgebase, tools, and much more.

Current Customers and Partners

Log in for full access

Log In

New to Red Hat?

Learn more about Red Hat subscriptions

Using a Red Hat product through a public cloud?

How to access this content