Torsten Hoefler 🇨🇭
@thoefler.bsky.social
Professor ETHZ, head of SPCL, Chief Architect ML at CSCS researching large-scale #HPC and #AI systems and #Climate computing - youtube: http://bit.ly/3h1VgIU
Rajeev Thakur is kicking off our Advanced MPI tutorial at #SC25. It's always an honor to teach this long standing tutorial with esteemed colleagues including Bill Gropp and Pavan Balaji. Great attendance 👌, still some seats in 122.
We're looking forward to a productive session.
We're looking forward to a productive session.
November 17, 2025 at 2:36 PM
Rajeev Thakur is kicking off our Advanced MPI tutorial at #SC25. It's always an honor to teach this long standing tutorial with esteemed colleagues including Bill Gropp and Pavan Balaji. Great attendance 👌, still some seats in 122.
We're looking forward to a productive session.
We're looking forward to a productive session.
Kurt Ferreira opens the 14th addition of our ROSS workshop at #SC25! Supercomputer operating systems and middleware going strong! Packed room as always 😀.
Starting with an invited talk by NVIDIA's Jeff Hammond on communication systems.
Trivia: he probably traveled furthest ✈️
Starting with an invited talk by NVIDIA's Jeff Hammond on communication systems.
Trivia: he probably traveled furthest ✈️
November 16, 2025 at 8:15 PM
Kurt Ferreira opens the 14th addition of our ROSS workshop at #SC25! Supercomputer operating systems and middleware going strong! Packed room as always 😀.
Starting with an invited talk by NVIDIA's Jeff Hammond on communication systems.
Trivia: he probably traveled furthest ✈️
Starting with an invited talk by NVIDIA's Jeff Hammond on communication systems.
Trivia: he probably traveled furthest ✈️
Arrived at #SC25 and just moved into the SPCL den 🏠 - our homebase for the whole on-site team this week. Readying ourselves for a crazy time - my three talks for tomorrow should mainly be set 😀.
Looking forward to seeing all of you in person - for those who I have not already met 🤝.
Looking forward to seeing all of you in person - for those who I have not already met 🤝.
November 16, 2025 at 3:17 PM
Arrived at #SC25 and just moved into the SPCL den 🏠 - our homebase for the whole on-site team this week. Readying ourselves for a crazy time - my three talks for tomorrow should mainly be set 😀.
Looking forward to seeing all of you in person - for those who I have not already met 🤝.
Looking forward to seeing all of you in person - for those who I have not already met 🤝.
Ilya Sutskever "Three lines of math can prove all of supervised learning. That's nice" (4:33)
"I have not seen an exposition of unsupervised learning that I found satisfying" (7:50)
Its optimization objective has little relation to the actual objective you care about
Watch: buff.ly/Bnvazym
"I have not seen an exposition of unsupervised learning that I found satisfying" (7:50)
Its optimization objective has little relation to the actual objective you care about
Watch: buff.ly/Bnvazym
November 10, 2025 at 6:00 AM
Ilya Sutskever "Three lines of math can prove all of supervised learning. That's nice" (4:33)
"I have not seen an exposition of unsupervised learning that I found satisfying" (7:50)
Its optimization objective has little relation to the actual objective you care about
Watch: buff.ly/Bnvazym
"I have not seen an exposition of unsupervised learning that I found satisfying" (7:50)
Its optimization objective has little relation to the actual objective you care about
Watch: buff.ly/Bnvazym
Can we build an #AI #Climate Scientist? Asked at the ADIA Lab Symposium in Abu Dhabi last week - now online at buff.ly/6igSeyg :-).
Much work to be done - this is outlining some directions of indicative results with a lot of potential to accelerate AI for Science.
Much work to be done - this is outlining some directions of indicative results with a lot of potential to accelerate AI for Science.
November 9, 2025 at 9:24 AM
Can we build an #AI #Climate Scientist? Asked at the ADIA Lab Symposium in Abu Dhabi last week - now online at buff.ly/6igSeyg :-).
Much work to be done - this is outlining some directions of indicative results with a lot of potential to accelerate AI for Science.
Much work to be done - this is outlining some directions of indicative results with a lot of potential to accelerate AI for Science.
Collaborator and friend Dan Alistarh talks at ETH about using the new NvFP4 and MXFP4 block formats for inference.
Some going from "terrible" accuracy to acceptable using micro rotations to smoothen outliers in blocks.
arxiv.org/abs/2509.23202
Great collaboration and cool stuff
Some going from "terrible" accuracy to acceptable using micro rotations to smoothen outliers in blocks.
arxiv.org/abs/2509.23202
Great collaboration and cool stuff
November 5, 2025 at 8:32 AM
Collaborator and friend Dan Alistarh talks at ETH about using the new NvFP4 and MXFP4 block formats for inference.
Some going from "terrible" accuracy to acceptable using micro rotations to smoothen outliers in blocks.
arxiv.org/abs/2509.23202
Great collaboration and cool stuff
Some going from "terrible" accuracy to acceptable using micro rotations to smoothen outliers in blocks.
arxiv.org/abs/2509.23202
Great collaboration and cool stuff
Keren Bergman at the 2nd EFCL Workshop: "Huawei combines 3x less performant GPUs with a photonic scale-up network to build higher performance PODs than Nvidia."
Nvidia moving towards CPO 😀. Optics everywhere in scale-out.
Nice overview of optical networking at all distances.
Nvidia moving towards CPO 😀. Optics everywhere in scale-out.
Nice overview of optical networking at all distances.
November 4, 2025 at 12:49 PM
Keren Bergman at the 2nd EFCL Workshop: "Huawei combines 3x less performant GPUs with a photonic scale-up network to build higher performance PODs than Nvidia."
Nvidia moving towards CPO 😀. Optics everywhere in scale-out.
Nice overview of optical networking at all distances.
Nvidia moving towards CPO 😀. Optics everywhere in scale-out.
Nice overview of optical networking at all distances.
I was very honored to meet Carnegie Mellon University's President, Dean of the School of CS, and its famous founder Raj Reddy to present a lecture named after him.
I tremendously enjoyed speaking with young students and faculty and the evening with CMU's leadership. Thanks for the invitation Raj!
I tremendously enjoyed speaking with young students and faculty and the evening with CMU's leadership. Thanks for the invitation Raj!
November 3, 2025 at 6:00 AM
I was very honored to meet Carnegie Mellon University's President, Dean of the School of CS, and its famous founder Raj Reddy to present a lecture named after him.
I tremendously enjoyed speaking with young students and faculty and the evening with CMU's leadership. Thanks for the invitation Raj!
I tremendously enjoyed speaking with young students and faculty and the evening with CMU's leadership. Thanks for the invitation Raj!
MIT's Sandy Pentland at ADIA Lab symposium: "Modern companies need to structure their incentives to coordiate teams instead of using strict and siloed hierarchies." Enable team leaders to do "what they think is right" instead of inefficient political discussions with leadership.
October 30, 2025 at 6:01 AM
MIT's Sandy Pentland at ADIA Lab symposium: "Modern companies need to structure their incentives to coordiate teams instead of using strict and siloed hierarchies." Enable team leaders to do "what they think is right" instead of inefficient political discussions with leadership.
One highlight of the ADIA Lab Symposium was Nobel Laureate Chu's talk towards Net-Zero emissions.
"China follows the US textbook from 100 years ago, when the US took products inventend in Europe, such as cars, industrialized and improved them. Now China takes things invented in the west..."
"China follows the US textbook from 100 years ago, when the US took products inventend in Europe, such as cars, industrialized and improved them. Now China takes things invented in the west..."
October 28, 2025 at 5:53 AM
One highlight of the ADIA Lab Symposium was Nobel Laureate Chu's talk towards Net-Zero emissions.
"China follows the US textbook from 100 years ago, when the US took products inventend in Europe, such as cars, industrialized and improved them. Now China takes things invented in the west..."
"China follows the US textbook from 100 years ago, when the US took products inventend in Europe, such as cars, industrialized and improved them. Now China takes things invented in the west..."
Just arrived at the ADIA Lab symposium in Abu Dhabi to listen to Horst Simon's introduction and Bjorn Stevens' keynote on how to compute the future climate! Featuring our Gordon Bell finalists 🌍🚀
Looking forward to speculating about how to create an #AI climate scientist 😀.
Looking forward to speculating about how to create an #AI climate scientist 😀.
October 27, 2025 at 6:25 AM
Just arrived at the ADIA Lab symposium in Abu Dhabi to listen to Horst Simon's introduction and Bjorn Stevens' keynote on how to compute the future climate! Featuring our Gordon Bell finalists 🌍🚀
Looking forward to speculating about how to create an #AI climate scientist 😀.
Looking forward to speculating about how to create an #AI climate scientist 😀.
Microsoft's Ultra Ethernet tutorial is now available on youtube 🎥!
Saurabh Dighe gives a brilliant motivation for Microsoft's "AI first datacenters" 🤖 followed by Abdul Kabbani and myself explaining the technical details and innovations of Ultra Ethernet supporting this goal 🫡.
buff.ly/IPN46ZR
Saurabh Dighe gives a brilliant motivation for Microsoft's "AI first datacenters" 🤖 followed by Abdul Kabbani and myself explaining the technical details and innovations of Ultra Ethernet supporting this goal 🫡.
buff.ly/IPN46ZR
October 20, 2025 at 5:00 AM
Microsoft's Ultra Ethernet tutorial is now available on youtube 🎥!
Saurabh Dighe gives a brilliant motivation for Microsoft's "AI first datacenters" 🤖 followed by Abdul Kabbani and myself explaining the technical details and innovations of Ultra Ethernet supporting this goal 🫡.
buff.ly/IPN46ZR
Saurabh Dighe gives a brilliant motivation for Microsoft's "AI first datacenters" 🤖 followed by Abdul Kabbani and myself explaining the technical details and innovations of Ultra Ethernet supporting this goal 🫡.
buff.ly/IPN46ZR
I'm excited to discuss whether we can build an "AI Climate Scientist" in my talk at the ADIA Lab Symposium 2025 🌎
Join us in Abu Dhabi or online from October 27–29!
Register here: buff.ly/gCP2K1z
#ADIALabSymposium2025
Join us in Abu Dhabi or online from October 27–29!
Register here: buff.ly/gCP2K1z
#ADIALabSymposium2025
October 15, 2025 at 10:47 AM
I'm excited to discuss whether we can build an "AI Climate Scientist" in my talk at the ADIA Lab Symposium 2025 🌎
Join us in Abu Dhabi or online from October 27–29!
Register here: buff.ly/gCP2K1z
#ADIALabSymposium2025
Join us in Abu Dhabi or online from October 27–29!
Register here: buff.ly/gCP2K1z
#ADIALabSymposium2025
I was shocked to see the first two people in my "masterclass" 🎓 on #AI networking with Ultra Ethernet at #HLF25: David Patterson and Bob Metcalfe 😅! Both Turing award winners - Bob being one of the inventors of Ethernet 🥹. Was great fun also with many enthusiastic students and great discussions 🚀.
October 13, 2025 at 5:00 AM
The first ADIA Lab transactions edited by Horst Simon arrive at my desk 📖.
An exciting mix of different science areas under the umbrella of advanced scientific computing and #AI 🎯. Congratulations to Horst and all co-authors 👏.
Onward 🚀!
An exciting mix of different science areas under the umbrella of advanced scientific computing and #AI 🎯. Congratulations to Horst and all co-authors 👏.
Onward 🚀!
October 6, 2025 at 5:00 AM
The first ADIA Lab transactions edited by Horst Simon arrive at my desk 📖.
An exciting mix of different science areas under the umbrella of advanced scientific computing and #AI 🎯. Congratulations to Horst and all co-authors 👏.
Onward 🚀!
An exciting mix of different science areas under the umbrella of advanced scientific computing and #AI 🎯. Congratulations to Horst and all co-authors 👏.
Onward 🚀!
I met many of my heroes at my first Heidelberg Laureate Forum #HLF25! Exciting discussions with 28 other laureates of the five highest awards in CS and Math and young researchers!
Watch my Spark talk at: buff.ly/SO6ntUb
Thanks to the HLF Foundation and Klaus Tschira Stiftung.
Watch my Spark talk at: buff.ly/SO6ntUb
Thanks to the HLF Foundation and Klaus Tschira Stiftung.
September 30, 2025 at 5:00 AM
I met many of my heroes at my first Heidelberg Laureate Forum #HLF25! Exciting discussions with 28 other laureates of the five highest awards in CS and Math and young researchers!
Watch my Spark talk at: buff.ly/SO6ntUb
Thanks to the HLF Foundation and Klaus Tschira Stiftung.
Watch my Spark talk at: buff.ly/SO6ntUb
Thanks to the HLF Foundation and Klaus Tschira Stiftung.
Happy 100th Birthday to Seymour Cray! 🎂
We took your relentless pursuit of speed and parallel processing, and built on your ideas to start the #AI revolution. Every neural network owes a debt to your chips.
Thanks for the gigahertz, Seymour! We're putting them to good use - your #LLM friend. 😉 #AI
We took your relentless pursuit of speed and parallel processing, and built on your ideas to start the #AI revolution. Every neural network owes a debt to your chips.
Thanks for the gigahertz, Seymour! We're putting them to good use - your #LLM friend. 😉 #AI
September 28, 2025 at 3:21 PM
Apertus, the Swiss Fully-Open-Data model downloaded more than 379k times - ~13 downloads per minute of up to 140+ GiB! Trending for some weeks among the world's top LLMs.
The techreport is now on arXiv: buff.ly/bvSioQH
The techreport is now on arXiv: buff.ly/bvSioQH
September 24, 2025 at 5:00 AM
Apertus, the Swiss Fully-Open-Data model downloaded more than 379k times - ~13 downloads per minute of up to 140+ GiB! Trending for some weeks among the world's top LLMs.
The techreport is now on arXiv: buff.ly/bvSioQH
The techreport is now on arXiv: buff.ly/bvSioQH
Bill Gropp speaks at the Modeling to Learning with #HPC #ICERM workshop about MPI performance, emphasizing the characteristic rendezvous "little blip" where bandwidth is lost in transition. This will completely go away to a smooth transition with Deferrable Sends in Ultra Ethernet!
buff.ly/0bEBb6y
buff.ly/0bEBb6y
September 22, 2025 at 5:00 AM
Bill Gropp speaks at the Modeling to Learning with #HPC #ICERM workshop about MPI performance, emphasizing the characteristic rendezvous "little blip" where bandwidth is lost in transition. This will completely go away to a smooth transition with Deferrable Sends in Ultra Ethernet!
buff.ly/0bEBb6y
buff.ly/0bEBb6y
Wonderful ICERM meeting on #HPC and #AI honoring Bill Gropp from NCSA. After crossing five US states by car (NJ, NY, CT, RI, MA) I met many old and new friends. Thanks to David Keyes to take the lead of this in a multi-year planning effort!
buff.ly/fu8h4mB
buff.ly/fu8h4mB
September 15, 2025 at 12:35 AM
Wonderful ICERM meeting on #HPC and #AI honoring Bill Gropp from NCSA. After crossing five US states by car (NJ, NY, CT, RI, MA) I met many old and new friends. Thanks to David Keyes to take the lead of this in a multi-year planning effort!
buff.ly/fu8h4mB
buff.ly/fu8h4mB
Was great to attend the Intel Academic Security workshop in Hillsboro, OR to talk about Marcin's work on performance aspects of Confidential HPC and AI systems as well as giving a keynote on UE from a security perspective. TSS rules - thanks to Eric Spada's leadership!
Read more: buff.ly/A9jczpC
Read more: buff.ly/A9jczpC
September 11, 2025 at 5:15 AM
Was great to attend the Intel Academic Security workshop in Hillsboro, OR to talk about Marcin's work on performance aspects of Confidential HPC and AI systems as well as giving a keynote on UE from a security perspective. TSS rules - thanks to Eric Spada's leadership!
Read more: buff.ly/A9jczpC
Read more: buff.ly/A9jczpC
Learn about Ultra Ethernet 1.0 from some of the authors.
Abdul Kabbani from Microsoft and I will be speaking about details of the 1.0 specification on Mon Sep. 8th 10am PST.
Join in-person at Microsoft Redmond building 99/1915 (open to public) or online buff.ly/vWIGYls
More info: buff.ly/ijiW5so
Abdul Kabbani from Microsoft and I will be speaking about details of the 1.0 specification on Mon Sep. 8th 10am PST.
Join in-person at Microsoft Redmond building 99/1915 (open to public) or online buff.ly/vWIGYls
More info: buff.ly/ijiW5so
September 3, 2025 at 9:00 AM
Learn about Ultra Ethernet 1.0 from some of the authors.
Abdul Kabbani from Microsoft and I will be speaking about details of the 1.0 specification on Mon Sep. 8th 10am PST.
Join in-person at Microsoft Redmond building 99/1915 (open to public) or online buff.ly/vWIGYls
More info: buff.ly/ijiW5so
Abdul Kabbani from Microsoft and I will be speaking about details of the 1.0 specification on Mon Sep. 8th 10am PST.
Join in-person at Microsoft Redmond building 99/1915 (open to public) or online buff.ly/vWIGYls
More info: buff.ly/ijiW5so
Congrats to Switzerland 🇨🇭 to its first sovereign #LLM #AI #chatbot. Apertus is a fully open (data) model trained on CSCS' 10,752 GH200 superchips #HPC.
Like a proper Swiss - multi-lingual, ethical, neutral, and open (direct) 😅!
Try: publicai.co
Download: buff.ly/sbZJOyo
Study: buff.ly/dHfcjkL
Like a proper Swiss - multi-lingual, ethical, neutral, and open (direct) 😅!
Try: publicai.co
Download: buff.ly/sbZJOyo
Study: buff.ly/dHfcjkL
September 3, 2025 at 5:10 AM
Congrats to Switzerland 🇨🇭 to its first sovereign #LLM #AI #chatbot. Apertus is a fully open (data) model trained on CSCS' 10,752 GH200 superchips #HPC.
Like a proper Swiss - multi-lingual, ethical, neutral, and open (direct) 😅!
Try: publicai.co
Download: buff.ly/sbZJOyo
Study: buff.ly/dHfcjkL
Like a proper Swiss - multi-lingual, ethical, neutral, and open (direct) 😅!
Try: publicai.co
Download: buff.ly/sbZJOyo
Study: buff.ly/dHfcjkL
The three tiers of openness for AI models: open weights, open source, and open data.
They determine scientific reproducibility, analyzability, and integrity of released models.
#AI for #Science
buff.ly/MfZwKM3
They determine scientific reproducibility, analyzability, and integrity of released models.
#AI for #Science
buff.ly/MfZwKM3
September 1, 2025 at 5:00 AM
The three tiers of openness for AI models: open weights, open source, and open data.
They determine scientific reproducibility, analyzability, and integrity of released models.
#AI for #Science
buff.ly/MfZwKM3
They determine scientific reproducibility, analyzability, and integrity of released models.
#AI for #Science
buff.ly/MfZwKM3