Supporting ethtool with Linux Integration Service

Open Source Technology Center

Microsoft

What is ethtool?• The man page description: ethtool is used to query and

control network device driver and hardware settings, particularly for wired Ethernet devices

• “ethtool” is a Linux utility which makes system calls into the kernel to change or display a set of tunable variables that impact the network features and performance• The number of send/receive queues of vRSS• The size of send/receive buffers• Turning on/off Large Send Offloading, etc.

What’s the Linux Integration Service?• The Linux Integration Service (LIS) includes a number of

kernel mode drivers in the Linux virtual machines (guests) running on Hyper-V hosts or Azure cloud

• Hyper-V is a native (bare metal) hypervisor (like XEN and VMware ESX) for running virtual machines

• The LIS drivers enable the Linux guests to run efficiently in the virtualized environment

What’s required to support ethtool?• A set of callback functions needs to be implemented in our

driver to support these tuning capabilities.• Implementing these functions requires knowledge of the

Linux kernel internals, and a detailed understanding of how our LIS source code works.

• As part of the Linux kernel, the developed code will be open-source with plans to be integrated into the kernel source tree.

• Mailing list: Linux Driver Project Developer List <driverdev-devel.linuxdriverproject.org>