Going ARM

Last week I attended the Arm Research Summit, and on Tuesday there was a panel session on using Arm hardware for performance, an effort known as GoingArm. You can watch the whole panel on youtube, from 2:12 onward (~1h30). All videos are available on the website. It was interesting to hear the opinions of people in […]

OpenHPC on AArch64

My current effort is to drive ARM hardware into the data centre, through HPC deployments, for the exascale challenge. Current Top500 clusters start from 0.5 petaflops, but the top 10 are between 10 and 90 petaflops, using as much as close to 20MW of combined power. Scaling up 10 ~ 100 times in performance towards exascale would […]

Trashing Chromebooks

At Linaro, we do lots of toolchain tests: GCC, LLVM, binutils, libraries and so on. Normally, you’d find a fast machine where you could build toolchains and run all the tests, integrated with some dispatch mechanism (like Jenkins). Normally, you’d have a vast choice of hardware to chose from, for each different form-factor (workstation, server, […]

Open Source and Profit

I have written extensively about free, open source software as a way of life, and now reading back my own articles of the past 7 years, I realize that I was wrong on some of the ideas, or in the state of the open source culture within business and around companies. I’ll make a bold […]

Uno score keeper

With the spring not coming soon, we had to improvise during the Easter break and play Uno every night. It’s a lot of fun, but it can take quite a while to find a piece of clean paper and a pen that works around the house, so I wondered if there was an app for […]

Distributed Compilation on a Pandaboard Cluster

This week I was experimenting with the distcc and Ninja on a Pandaboard cluster and it behaves exactly as I expected, which is a good thing, but it might not be what I was looking for, which is not. 😉 Long story short, our LLVM buildbots were running very slow, from 3 to 4.5 hours to […]

LLVM Vectorizer

Now that I’m back working full-time with LLVM, it’s time to get some numbers about performance on ARM. I’ve been digging the new LLVM loop vectorizer and I have to say, I’m impressed. The code is well structured, extensible and above all, sensible. There are lots of room for improvement, and the code is simple […]

Declaration of Internet Freedom

We stand for a free and open Internet. We support transparent and participatory processes for making Internet policy and the establishment of five basic principles: Expression: Don’t censor the Internet. Access: Promote universal access to fast and affordable networks. Openness: Keep the Internet an open network where everyone is free to connect, communicate, write, read, watch, speak, listen, […]

K-means clustering

Clustering algorithms can be used with many types of data, as long as you have means to distribute them in a space, where there is the concept of distance. Vectors are obvious choices, but not everything can be represented into N-dimensional points. Another way to plot data, that is much closer to real data, is […]

Google knows what you searched last summer

Despise all the controversy, Google started his new Privacy Policy last Thursday and whether you like it or not, you are being watched. Being realistic, this is not far from what they were already doing: Google already tracked your searches, what you are watching on Youtube or your emails. But before March, 1st, Google Plus, […]