Dr. Neil Gunther
Performance analyst, 'rocket scientist' & Xerox PARC alum 🇦🇺🇺🇸 Consultant, author, teacher, physics, math, stats, chem and some 🎸 performance too.
- Ordinary AI output requires extraordinary human verification. (Apologies to C. Sagan)
- DR still in progress for AMZN.com itself ... 🧐
- Productivity: If you want to be more productive, go to sleep. www.perfdynamics.com/Manifesto/gc...
- Some performance consequences often overlooked in redundancy plans perfdynamics.blogspot.com/2014/03/perf...
- Out of The Queue Comes ... Amdahl’s Law! www.perfdynamics.com/Papers/amdsy...
- RIP James Lovell, commander of Apollo 13 (played by Tom Hanks in the movie of the same name), has died at age 97.
- A. Displaying metrics, errors, etc., is not the same thing as displaying metric errors. 1. How it is (old school top) CPU usage: 5.79 %usr, 4.51 %sys, 89.68 %idl 2. How it could be (nay, SHOULD be) CPU usage: 5.79 ± 0.29 %usr, 4.51 ± 0.23 %sys, 89.68 ± 4.48 %idl
- Online classroom buzz www.perfdynamics.com/Classes/comm... What Guerrilla Grads are saying about why you should become an alumnus. Enroll here www.perfdynamics.com/Classes/sche... 🎓 #performance #engineering #capacity #management #marketplace #trends #GCAP #GDAT #PDQW
- PSA: New open access Journal of Systems Scalability launching. Editor-in-Chief: Carlos Juiz www.icck.org/jss #systems #architecture #performance #scalability
- GCAP Day 10. What you missed: ❥ Avalanche vs. Paxos coordination scalability ❥ Memcache scalability analysis with USL ❥ Queueing models of Kubernetes control and data planes ❥ Class dismissed 📚 🎓🍻
- Never let reality get in the way of a good performance model.
- GCAP Day 9. What you missed: ❥ Rate limiting services via Guerrilla queueing models ❥ Performance visualization tools ❥ Zookeeper scalability analysis with the USL www.perfdynamics.com/Manifesto/US...
- GCAP Day 8. What you missed: ❥ Linear vs Dynamic programming ❥ Benchmarking/load testing prats and pitfalls ❥ Prelim discussion about Kefka, Kubernetes ❥ What kind of scheduler is in the K8s control plane?
- GCAP Day 7. What you missed: ❥ Python least_squares() seems to be a bloated implementation of codes in the "Numerical Recipes" book. ❥ To apply the USL, use curve_fit() instead. ❥ Multivariate regression: How to reattach (noisy) fingers to amputated daily "numero uno" data
- GCAP Day 6. What you missed: ❥ USL scalability analysis lnkd.in/gxaaAiww ❥ Student gets PDQ 7.0 running on Python 3.12 👏🎉 lnkd.in/gPzzHiez ❥ Homework Q-5 solved (a) analytically (b) cf. with corresponding PyDQ model - Discussed why analytic calculation was wrong
- Ditto for the performance analysis & capacity planning of computer systems in general: - Assume failure - Plan for resilience - Monitor everything - Analyze and predict performance and capacity - Have an exceptional performance team of skilled experts lnkd.in/g8eGRnYq
- RIP Chuck Mangione www.youtube.com/watch?v=c4el...
- #TIL Product Solutions Physicist 😳
- I recently discovered the original 1992 paper where I first introduced the concept of barycentric coordinates for visualizing multiprocessor/multicore performance. www.perfdynamics.com/papers.pdf More modern renditions (animations) can be viewed here www.perfdynamics.com/Tools/tools....
- Yep.
- Guerrilla training classes (GCAP) online are brutal. Despite the rumors, there are no long lunches. Only performance zealots should apply. Next class starts July 21, 2025. www.perfdynamics.com/Classes/sche... #Performance #Training
- Guerrilla Capacity Planning (GCAP) Online — EU Edition — registration is now OPEN Dates: July 21 through August 1, 2025 Times: 1500 - 1900 CET www.perfdynamics.com/Classes/sche... Click on the DETAILS box (at the RHS) to register www.eventbrite.com/e/guerrilla-...
- TIL: Many happy returns of the day & The spirit of @Lyft lifts your spirits. 1. My only phone slid out of my pants' pocket during a Lyft ride this morning. Fortunately, Lyft has a "Help/Lost my phone" web page that I could access from my laptop.
- Bill Atkinson, he of QuickDraw and MacPaint fame, has died at 74 of pancreatic cancer. news.ycombinator.com/item?id=4421...
- Interesting to see LoadRunner is still alive. I haven't heard about LR anything in a long time, let alone LR Cloud. #load #test #performance www.linkedin.com/pulse/loadru...
- Best Boggle board found after 20 years of casual computer searching www.bbc.co.uk/sounds/play/... starting @ 19:08 - Peak word: "replastering"
- "DeepSeek-V3: Scaling Challenges," in Proc. 52nd Intl. Symp. Comp. Arch. (ISCA 2025), June 21-25, Tokyo, Japan. #scalability #Performance #GenAI #AI arxiv.org/pdf/2505.093...
- Meantime on Kilauea ...
- How to Quantify Scalability: Synopsis of The Universal Scalability Law (USL) has just been posted in PDF format for improved readability. I did this post haste so, reporting any typos, broken links, etc., is always appreciated. www.perfdynamics.com/Manifesto/US... #performance
- 1/2 Just updated my "Performance Ponderings" page. It covers my performance analysis papers published over 35 yrs. 😳 You may be thinking: Who cares about performance analysis that is so dated!? Amazingly, performance analysis (done right) is often not technology-dependent but time-independent.
- My ICPE/WEPPE 2025 presentation slides speakerdeck.com/drqz/guerril... and the corresponding ACM paper dl.acm.org/doi/pdf/10.1...
- ICPE/WEPPE Monday, May 5th @ 9am EDT esulabsolutions.godaddysites.com/sponsored-ev...
- Just joined ICPE 2025 conference Slack.
- PSA: Skype — the rotary phone of VOIP — will no longer be in service as of this coming Monday (May 5th, 2025).
- OMG: Olo My Green !!! A never-before-seen color (christened "olo") has been produced by a team at @UCBerkeley www.science.org/doi/10.1126/... #color #science
- ChatGPT, the fortune cookie of AI 🥁
- Why are there no giants? The Data Analytics of Application Scaling speakerdeck.com/drqz/the-dat... #performance #engineering