Physical Host Metrics in Ceilometer – An Openstack Liberty Tale

This post is about the errors while getting physical machine metrics with ceilometer specifically  Openstack Liberty. Simply errors can be:

– No metrics shown in:

ceilometer meter-list

specifically metrics listed below:

  • compute.node.cpu.frequency
  • compute.node.cpu.idle.percent
  • compute.node.cpu.idle.time
  • compute.node.cpu.iowait.percent
  • compute.node.cpu.iowait.time

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3D Rotations about Arbitrary Axis – Euler–Rodrigues and Matrix Methods

Code is written in python, uses pyglet to draw lines and vertices. All vertex calculations is done without using 3D methods of any library.

Euler-Roudrigues rotation and rotation about x, y, and z axis are given separately. Rotation method can be selected from code.

Left, right, up, and down arrow keys moves the cube.

x, y, and z keys rotates cube with the specified axes.

This code is for demonstration purposes only, so it is neither optimal nor complete. Use it as is.

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