Linux-Kongress 2009 Tuning Gathering
The Linux-Kongress is traditionally where kernel developers exchange honors and advice about new features and enhancements. This year a number of speakers presented performance improvement data and discussed what aspects of Linux can be drawn out even more.
The annual gathering organized by the German Unix Users Group (GUUG) took place this year in Dresden, the German city on the river Elbe, October 27-30. Around 100 participates took part in the steadily more familiar event. After two days of tutorials another two days of technical sessions included 25 talks on two parallel tracks. Linux Foundation's Ted Ts'o, in his keynote, preached a bit to the choir in listing the good reasons behind the Linux free development model. Felix "Fefe" von Leitner, on the other hand, provided some fascinating research results after examining a number of compilers for what they can produce in machine code from typical code fragments. He was surprized to find that the oft derided GNU Compiler Collection (GCC) in many cases does some clever optimization.
Specialized compilers such as Intel's Compiler Suite (ICC) may effectively bring in such architecturally typical properties as vectorization, but can't do the same tricks in the details. As von Leitner suggested wryly to Linux Magazine Online, "GCC as an open source project has practically unlimited resources in doctoral candidates at universities." All in all he recommends that developers rather write understandable code than to optimize it by hand: "The compiler wins best with efficient code."
Kernel hacker Andi Kleen adds that von Leitner's statement applies only on a limited scale to programs and the Linux kernel when it comes to developing steadily growing multi-core systems. Kleen, who has long been responsible for Linux's 64-bit port, is now on Intel's payroll. He suggested that many of today's CPU providers get performance increases out of their processors in much greater degree from multi-cores rather than clock rates. So far weather simulation supercomputers doing the same parallel processing over and over again have profited from this approach. But since other systems reaching to desktops and netbooks can also benefit from multi-core, developers should, according to Kleen, take a stronger parallelization tack. A lot can still only be done by hand, despite the many libraries Kleen mentioned to Linux Magazine Online.
A central role to parallel processing applies to locks, which ensure that multi-cores can simultaneously access shared resources to find inconsistent data. Kleen emphasized the importance of implementing these locks as granularly as possible, such as by locking subtrees or branches instead of the entire tree or all functions that operate on the structure. Another problem is the communication expenditure among the cores. The worst case is that processors wait for each other's cache to empty unnecessarily, leading to ever increasing overhead.
Kleen meanwhile looks upon the kernel with some satisfaction. It already uses modern forms of locks that go into sleep mode. However, developers in userland still have ways to go in implementing them. Tips that Kleen has about his implementation should appear on the Linux-Kongress webpages as soon as GUUG organizer Wolfgang Stief posts them in the coming week.
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
Juno Computers Launches Another Linux Laptop
If you're looking for a powerhouse laptop that runs Ubuntu, the Juno Computers Neptune 17 v6 should be on your radar.
-
ZorinOS 17.1 Released, Includes Improved Windows App Support
If you need or desire to run Windows applications on Linux, there's one distribution intent on making that easier for you and its new release further improves that feature.
-
Linux Market Share Surpasses 4% for the First Time
Look out Windows and macOS, Linux is on the rise and has even topped ChromeOS to become the fourth most widely used OS around the globe.
-
KDE’s Plasma 6 Officially Available
KDE’s Plasma 6.0 "Megarelease" has happened, and it's brimming with new features, polish, and performance.
-
Latest Version of Tails Unleashed
Tails 6.0 is based on Debian 12 and includes GNOME 43.
-
KDE Announces New Slimbook V with Plenty of Power and KDE’s Plasma 6
If you're a fan of KDE Plasma, you'll be thrilled to hear they've announced a new Slimbook with an AMD CPU and the latest version of KDE Plasma desktop.
-
Monthly Sponsorship Includes Early Access to elementary OS 8
If you want to get a glimpse of what's in the pipeline for elementary OS 8, just set up a monthly sponsorship to help fund its continued existence.
-
DebConf24 to be Held in South Korea
Busan will be the location of the latest DebConf running July 28 through August 4
-
Fedora Unleashes Atomic Desktops
Fedora has combined its solid distribution with rpm-ostree system to make it possible to deliver a new family of Fedora spins, called Fedora Atomic Desktops.
-
Bootloader Vulnerability Affects Nearly All Linux Distributions
The developers of shim have released a version to fix numerous security flaws, including one that could enable remote control execution of malicious code under certain circumstances.