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

How it works...

We can see what I/O scheduler the kernel is currently using by examining the scheduler file in the /sys virtual filesystem. In step 1, we see that it's the cfq scheduler. We then proceed to change the I/O scheduler on the running in step 2. Please keep in mind that changing the scheduler on demand like that will not persist server restarts. In steps 3 and 4, we modify the GRUB configuration which will append the new scheduler information to the kernel boot instructions. Restarting the server or the virtual machine will now select the new I/O scheduler.

If running multiple virtual machines on the same host, it might be useful to give more I/O priority to some of them based on certain criteria, such as time of day and VM workload. ...

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