
Troublemaker | Computer Architect | @Arm Servers Architect @Google | Previously @RedHat, @Nuvia_Inc | Runner | Author | All views my own | #ArmServers
Cambridge, MA, USA
Joined May 2008
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Jon Masters 🏴☠️ retweeted
Fun fact - 80% of Apple’s compute capacity is used to render Craig Federighi’s hair
Jon Masters 🏴☠️ retweeted
A good bridge CPU is not easy to make. AMD succeeded (x86-32/64 not really 2 distinct ISAs). Itanium failed at this (x86-32 ISA part was significantly underpowered).
newsroom.ibm.com/2026-08-24-…
Jon Masters 🏴☠️ retweeted
If you wanna follow #HotChips then you should follow @ServeTheHome! I am following remotely this year.
At Hot Chips 2026, IBM showed a crazy new IBM Z CPU that will support IBM Z and @Arm instruction sets natively. This is almost mind-blowing what the @IBM engineers did here. New AI acceleration with redundancy and HBM 3e as well. Wow. servethehome.com/ibm-z-and-l…
Jon Masters 🏴☠️ retweeted
Wait a second, are you telling me years of effort, thought, and dedication to creating software is in fact better than your weekends slop cannon?
I refuse to believe it
Jon Masters 🏴☠️ retweeted
Ability to learn from younger and less experienced colleagues is the true sign of seniority.
Jon Masters 🏴☠️ retweeted
Every few weeks someone posts a graph showing that C++ is 50x faster than Python because they wrote a program that counts to 1000000000. This is then presented as a profound statement about programming languages rather than what it actually is: a measurement of how fast two runtimes execute a completely useless loop
The first problem is that the benchmark is usually measuring something other than what the author thinks it is measuring. Python is mostly paying interpreter overhead. C++ is mostly showing off compiler optimizations. In many cases the compiler can look at the loop, realize it accomplishes nothing, and replace your billion iteration masterpiece with effectively no code at all.
The second problem is that nobody is paid to count to a billion. I mean at least 99.99% of the people ( I am looking at you, op)
real programs spend time waiting for db calls, parsing json, reading files, allocating memory, talking to networks, decompressing data, rendering frames, or doing actual computation. A benchmark that does none of these things tells us approximately nothing about how those programs will behave.
This leaves a bigger impact on someone who is new to engineering and this stuff. They will see this post and go - "Oh wow python is trash"
The question is never "how fast is C++?" The question is "how fast is C++ at what?" Performance is a property of a workload, not a programming language. Once you remove the workload from the discussion, all you're left with is benchmark theater and a graph optimized for engagement.
If your benchmark doesn't resemble any real problem anyone actually has, you're not measuring performance. You're measuring how creatively you can waste a CPU's time (:
Requesting @cmuratori to take inspiration from @rfleury and bless us with delete your accounts on these stupid posts.
Jon Masters 🏴☠️ retweeted
This is the slide that Jensen needed to show 20 minutes ago... It helps to explain what needs to be on a CPU and what needs a GPU, or more, like DPU or Networking. #Computex2026 #GTCTaipei
Jon Masters 🏴☠️ retweeted
I built an operating system just for reverse engineering CPUs.
We used it to poke around the branch predictors on Apple Silicon and found some cool stuff (including Phantom fetches!).
See what we found here: csail.mit.edu/news/study-how…
Jon Masters 🏴☠️ retweeted
Barney Frank was one of a kind. For more than three decades in Congress, he fought tirelessly for the people of Massachusetts, helped make housing more affordable, stood up for the rights of LGBTQ+ Americans, and helped pass one of the most sweeping financial reforms in history designed to protect consumers and prevent another financial crisis. Barney’s passion and wit were second to none, and our thoughts are with his family today.
Jon Masters 🏴☠️ retweeted

@fclc cmp lea char@FelixCLC_May 19
🇨🇦
CanadaConnected via Canada App StoreAccount-level information, not a live location or per-post device.
WE HAVE TMUX
LEARN TO USE TMUX
Jon Masters 🏴☠️ retweeted
new yorker visits san francisco 😅
“It's a little freaky not to have a driver,” says @AndersonCooper as he rides in a Waymo robotaxi. cbsn.ws/4ut1Hb6
Jon Masters 🏴☠️ retweeted
My Claude subscription running out of tokens is how AI reminds me of my mortality.
Jon Masters 🏴☠️ retweeted
Replying to @beaversteever @jonmasters
Jon Masters 🏴☠️ retweeted
La petite info mignonne du jour : aujourd'hui le 05/05, le circuit intégré le plus célèbre de l'histoire de l'électronique, le NE 555, fête ses 55 ans.
Voilà c'est tout, vous pouvez continuer à faire ce que vous faisiez 😊
Jon Masters 🏴☠️ retweeted
Love seeing Naomi Osaka honor the CLRS Algorithms textbook at this year's Met Gala


































