Linux Kernel 6.10 is Released: This is What's New for Compute Express Link (CXL)

How to Build acpidump from Source and use it to Debug Complex CXL and PCI Issues

• Steve Scargall
• Linux , Cxl

This article is a detailed guide on how to build the latest version of the acpidump tool from its source code. While many Linux distributions, like Ubuntu, offer a packaged version of this utility, it’s often outdated. For developers and enthusiasts working with modern hardware features, particularly those related to Compute Express Link (CXL), having the most current version is essential.

Before you begin, it’s important to remove any old, conflicting versions of the tools. If you have previously installed the acpica-tools package from your distribution’s repository, you should remove it to prevent conflicts.

How To Build a custom Linux Kernel to test Data Access Monitor (DAMON)

• Steve Scargall
• How to , Linux

DAMON is a data access monitoring framework subsystem for the Linux kernel. DAMON (Data Access MONitor) tool monitors memory access patterns specific to user-space processes introduced in Linux kernel 5.15 LTS, such as operation schemes, physical memory monitoring, and proactive memory reclamation. It was designed and implemented by Amazon AWS Labs and upstreamed into the 5.15 Kernel , but it was not enabled by default.cd /boot

Keen to try this new feature to identify the working set size (Active Memory) of a server or process, this post documents the steps I took to build a custom Kernel with DAMON enabled using Fedora Server 35.

A Practical Guide to Identify Compute Express Link (CXL) Devices in Your Server

• Steve Scargall
• How to , Linux

In this article, we will provide four methods for identifying CXL devices in your server and how to determine which CPU socket and NUMA node each CXL device is connected. We will use CXL memory expansion (CXL.mem) devices for this article. The server was running Ubuntu 22.04.2 (Jammy Jellyfish) with Kernel 6.3 and ‘cxl-cli ’ version 75 built from source code. Many of the procedures will work on Kernel versions 5.16 or newer.