Use elevator=noop For Linux Virtual Machines
This is post #6 in my December 2013 series about Linux Virtual Machine Performance Tuning. For more, please see the tag “Linux VM Performance Tuning.” Modern operating systems are fairly modular, and often have different modules to deal with memory, network I/O, and CPU scheduling. Disk I/O is no exception under Linux, as there are usually four different schedulers a sysadmin can choose from. Red Hat had a nice write-up on these a few years back and it remains relevant today: The Completely Fair Queuing (CFQ) scheduler is the default algorithm in Red Hat Enterprise Linux 4. As the name implies, CFQ maintains a scalable per-process I/O queue and attempts to distribute the available I/O bandwidth equally among all I/O …