Learning PF_RING and netmap

Paul E. Mc Kenney: Stupid RCU Tricks: Which tests do I run???
The rcutorture test suite has quite a few options, including locktorture, rcuscale, refscale, and scftorture in addition to rcutorture itself. These tests can be run with the assistance of either KASAN or KCSAN. Given that RCU contains kernel modules, there is the occasional need for an allmodconfig build. Testing of kvfree_rcu() is currently a special case […]
Brendan Gregg: Poor Disk Performance
People often tell me they don't understand performance tool output because they can't tell what's "good" or "bad." It can be hard as performance is subjective. What's good for one user may be bad for another. There are also cases where I can't tell either: The tools only provide clues for further analysis. I recen […]
Matthew Garrett: More doorbell adventures
Back in my last post on this topic, I'd got shell on my doorbell but hadn't figured out why the HTTP callbacks weren't always firing. I still haven't, but I have learned some more things.Doorbird sell a chime, a network connected device that is signalled by the doorbell when someone pushes a button. It costs about $150, which seems excess […]
Linux Plumbers Conference: Dates for Virtual Linux Plumbers now 20-24 September
We took a look at all the events that were announced at the same time as OSS, including KVM Forum. The dates 20-24 September still seem to be clear of conference overlaps so we thought we’d grab them for Plumbers before someone else does. We also thought the timezone last year (Atlantic, 1h ahead of US Eastern and 5h behind central European) worked well, so […]
Linux Plumbers Conference: Containers and Checkpoint/Restore Microconference Accepted into 2021 Linux Plumbers Conference
We are pleased to announce that the Containers and Checkpoint/Restore Microconference has been accepted into the 2021 Linux Plumbers Conference! The Containers and Checkpoint/Restore micro-conference brings together kernel developers, runtime maintainers, and developers working on container- and sandboxing related technologies in general to discuss current p […]
Linux Plumbers Conference: Linux Plumbers Goes Fully Virtual
You may have noticed that the Linux Foundation has announced moving OSS+ELC from Dublin to Seattle, WA due to survey results and vaccination rates in Europe. Since we agreed to co-locate with OSS+ELC this year, we’ve been debating following suit or going virtual. Unfortunately, the safety protocols imposed by event venues in the US require masks and social d […]
Pete Zaitcev: Swift in 2021
A developer meet-up for OpenStack, known as PTG, occurred a week ago. I attended the Swift track, where somewhat to my surprise we had two new contributors show up. I got into a habit of telling people that I did not want Swift to end like AFS: develop great software and dead, with nobody using it. Today I looked it up, and what do you know: OpenAFS made a r […]
Paul E. Mc Kenney: Stupid RCU Tricks: A tour through rcutorture
Although Linux-kernel RCU gets most of the attention, without rcutorture, RCU would not be what it is today. To see this, note that the old saying “If it ain't tested, it don't work!” is if anything more valid today than it was back then. After all, software has not gotten any simpler, workloads have not become less demanding, and systems have not […]
Paul E. Mc Kenney: Stupid RCU Tricks: The design of rcutorture
This installment of the rcutorture series takes a high-level look at its design. At the highest level, rcutorture is a stress test with a few unit-test components thrown in for good measure. It also includes scripts to handle both single-system and distributed testing. All of this code is of course paying homage to the many moods of Mr. Murphy.The Many Moods […]
Matthew Garrett: An accidental bootsplash
Back in 2005 we had Debconf in Helsinki. Earlier in the year I'd ended up invited to Canonical's Ubuntu Down Under event in Sydney, and one of the things we'd tried to design was a reasonable graphical boot environment that could also display status messages. The design constraints were awkward - we wanted it to be entirely in userland (so we […]