O'Reilly logo

KVM Virtualization Cookbook by Konstantin Ivanov

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Tuning the kernel for low I/O latency

In this recipe, we are going to cover some of the disk performance optimization techniques by selecting an I/O scheduler and tuning the block I/O using Linux control groups, for the virtual guest and the host.

There are three I/O schedulers to choose from on the host OS and in the KVM instance:

  • noop: This is one of the simplest kernel schedulers; it works by inserting all incoming I/O requests into a simple FIFO (First In, First Out) queue. This scheduler is useful when the host OS should not attempt to reorder I/O requests when multiple virtual machines are running.
  • deadline: This scheduler imposes a deadline on all I/O operations to prevent starvation of requests, giving priority to read requests, ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required