Checking for Constant Time Stamp Counter

A Constant Time Stamp Counter is included in more recent Intel Processors (TSC) to reads at the processor’s maximum rate regardless of the actual CPU running rate. While this makes time keeping more consistent, but it can skew benchmarks, where a certain amount of spin-up time is spent at a lower clock rate before the OS switches the processor to the higher rate. For more information on Time Stamp Counter, do look at Time Stamp Counter (wikipedia)

To check whether your CPU support TSC, you can issue the command

# grep -q constant_tsc /proc/cpuinfo && echo "Constant TSC detected" || echo "No Constant TSC Detected"

Creation of Logical Networks on RHEV

Logical Networks allow segregation of different types of traffic. According to Red Hat Training Manual, it is recommended to have 3 types of network

  1. Management Network – Network to connect hypervisor (RHEV-H) nodes to the RHEV Manager
  2. Storage Network – Network to connect RHEV-H  to NFS and iSCSI. If you are using FC, there is no need to create a separate network since it is using SAN
  3. Public Network –  Connect the Gateway Router, the RHEV-M systems and RHEV-H Nodes


Configure Logical Networks

Data Centre > Networks > New Loginal Networks



Configure Network Mac Address Pool

1. View Current Settings

# rhevm-config -g MacPoolRanges
MacPoolRanges: 00:1a:4a:9f:7e:00-00:1a:4a:9f:7e:ff version: general

2. Set the Mac range to 52:54:00:56:00:01 – 52:54:00:56:00:FF

# rhevm-config -s MacPoolRanges=52:54:00:56:00:01-52:54:00:56:00:FF

3. Restart ovirt-engine engine

# service ovirt-engine restart