Altair® Radioss® is an industry-proven analysis solution that helps users evaluate and optimize product performance for highly nonlinear problems under dynamic loadings. For more than 30 years, organizations have used Altair Radioss to streamline and optimize the digital design process, replace costly physical tests with quick and efficient simulation, and speed up design optimization iterations.
OpenRadioss is the publicly available open-source code base that a worldwide community of researchers, software developers, and industry leaders are enhancing every day. OpenRadioss is changing the game by empowering users to make rapid contributions that tackle the latest challenges brought on by rapidly evolving technologies like battery development, lightweight materials and composites, human body models and biomaterials, autonomous driving and flight, as well as the desire to give passengers the safest environment possible via virtual testing.
With OpenRadioss, scientists and technologists can focus their research on a stable code base under professional maintenance that benefits from the large library of existing finite element capabilities and the continuous integration and continuous development tools provided to contributors.
The next generation Linux workstation, designed for reliability, performance, and sustainability.
Originally posted at https:/opensource.com/article/19/8/introduction-bpftrace.
bpftrace is a new open source tracer for Linux for analyzing production performance problems and troubleshooting software. It is used by and has had contributions from many companies including Netfilx, Facebook, Red Hat, Shopify, and others. It was created by Alastair Robertson, a talented UK-based developer who has previously won various coding competitions.
Linux already has many performance tools, but these are often counter-based and have limited visibility. For example, iostat(1), or a monitoring agent, may tell you your average disk latency, but not the distribution of this latency. Distributions can reveal multiple modes, or outliers, either of which may be the real cause of your performance problems. bpftrace is suited for this kind of analysis: decomposing metrics into distributions or per-event logs, and creating new metrics for visibility into blind spots.
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.
When you insert data into a database and run COMMIT you expect things to be there: Atomically, Consistent, Isolated and Durable, like Codd commanded us 40 years ago, but also quickly. There is a surprising amount of sophistication being poured into this, but since I do not want to shame MongoDB and Redis developers in this post, I am not going to talk about that much in this place.
We are instead trying to understand what our databases are doing all day, from the point of view of the storage stack.
A tool to monitor I/O latency in real time. It shows disk latency in the same way as ping shows network latency.
Homepage: https://github.com/koct9i/ioping/ (migrated from http://code.google.com/p/ioping/)
Please send your patches, issues and questions to https://github.com/koct9i/ioping/issues/
Mit ein paar kleinen Eingriffen in die Jitsi-Meet-Konfiguration könnt ihr die Leistung optimieren. Insbesondere Video-Konferenzen mit mehreren Teilnehmern profitieren von den Einstellungen.
Öffnet dazu die config.js-Datei von Jitsi Meet:
bpftrace is a high-level tracing language for Linux enhanced Berkeley Packet Filter (eBPF) available in recent Linux kernels (4.x). bpftrace uses LLVM as a backend to compile scripts to BPF-bytecode and makes use of BCC for interacting with the Linux BPF system, as well as existing Linux tracing capabilities: kernel dynamic tracing (kprobes), user-level dynamic tracing (uprobes), and tracepoints. The bpftrace language is inspired by awk and C, and predecessor tracers such as DTrace and SystemTap. bpftrace was created by Alastair Robertson.
We know that using swap space instead of RAM (memory) can severely slow down the performance of Linux. So then, one might ask, since I have more than enough memory available, wouldn’t it better to remove swap space completely? The short answer is, No. There are performance benefits when swap is enabled, even when you have more than enough ram.
Shell script to test the performance of the most popular DNS resolvers from your location.
Includes by default:
CloudFlare 1.1.1.1
Google 8.8.8.8
Quad9 9.9.9.9
OpenDNS
Norton
CleanBrowsing
Yandex
AdGuard
Neustar
ComodoLook deeply into your Linux code with these Berkeley Packet Filter (BPF) Compiler Collection (bcc) tools.
I was in Prague last month for the 2017 edition of the KVM Forum. There I gave a talk about some of the work that I’ve been doing this year to improve the qcow2 file format used by QEMU for storing disk images. The focus of my work is to make qcow2 faster and to reduce its memory requirements.
I was in Prague last month for the 2017 edition of the KVM Forum. There I gave a talk about some of the work that I’ve been doing this year to improve the qcow2 file format used by QEMU for storing disk images. The focus of my work is to make qcow2 faster and to reduce its memory requirements.
Collecting benchmark results is the first step to solving disk I/O performance problems. Unfortunately, many bug reports and performance investigations fall down at the first step because bogus benchmark data is collected. This post explains common mistakes when running disk I/O benchmarks.
This is the last post in a 4-part series about Kubernetes monitoring. Part 1 discusses how Kubernetes changes your monitoring strategies, Part 2 explores Kubernetes metrics and events you should monitor, Part 3 covers the different ways to collect that data, and this post details how to monitor Kubernetes performance with Datadog.
Siege is an http load testing and benchmarking utility. It was designed to let web developers measure their code under duress, to see how it will stand up to load on the internet. Siege supports basic authentication, cookies, HTTP, HTTPS and FTP protocols. It lets its user hit a server with a configurable number of simulated clients. Those clients place the server “under siege.”
Veröffentlicht am 21.12.2016
Demo from the USENIX/LISA 2016 talk: Linux 4.X Tracing Tools: Using BPF Superpowers. Full talk slides and official video will be available at https://www.usenix.org/conference/lis... . This video is the 15 (more like 18) minute demo that spans ftrace, perf, and BPF. LISA is a registered trademark of the USENIX Association and is used in this video with permission.




