Performance Optimisation

In Best Practices for running Linux on Hyper-V, Microsoft recommends the use of the NOOP scheduler for better disk I/O performance. To use this scheduler in Debian, the elevator=noop instruction needs to be added to kernel parameters line in the grub configuration file.

Use the following instructions to enable the NOOP schedule for better disk I/O performance.

1. Determine which I/O Scheduler is currently in use, using the following command:

   cat /sys/block/sda/queue/scheduler

   The command will show the Completely Fair Queuing scheduler is in use by default:

   noop deadline [cfq]

2. Enable the NOOP scheduler, using the following commands:

   sudo sed -i '/GRUB_CMDLINE_LINUX_DEFAULT/ s/^\(.*\)\("\)/\1 elevator=noop\2/' /etc/default/grub
   sudo update-grub

3. Reboot the virtual machine so this change to the scheduler can take affect, using the following command:

   sudo reboot

   The virtual machine will reboot.

4. Once rebooted, login and determine which I/O Scheduler is in use, using the following command:

   cat /sys/block/sda/queue/scheduler

   The command will now indicate that the noop scheduler is in use:

   [noop] deadline cfq

Your virtual Debian machine on Hyper-V is now ready to go!