Brendan Gregg
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13 March
7 February
6 February
From one piece Why I joined OpenAI 3 beliefs, in the piece's order there
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korrents.com
eBPF, Ftrace, and hardware performance counters are proven tools for finding datacenter performance wins.Their words
given those technologies are proven for finding datacenter performance wins, it seems likely
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Their words
I've realized that performance engineering as we know it may not be enough - I'm thinking of new engineering methods so that we can find bigger optimizations than we have before, and find them faster.
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korrents.com
AI datacenter growth makes performance engineering critical for saving the planet, not just cutting costs.Their words
The staggering and fast-growing cost of AI datacenters is a call for performance engineering like no other in history; it's not just about saving costs - it's about saving the planet.
5 December 2025
4 December 2025
27 November 2025
From one piece On "AI Brendans" or "Virtual Brendans" 3 beliefs, in the piece's order there
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korrents.com
Widespread AI-driven performance tuning agents will meaningfully reduce global energy waste.Their words
In future there will be AI performance agents that can be run on everything, helping to save the planet by reducing energy usage.
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korrents.com
Relying on AI to replace performance engineers reduces an organization's overall technical expertise over time.Their words
If a company spends less on performance engineers as it's considered AI'd, it will reduce the company's effective "performance IQ."
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korrents.com
AI agents trained on an expert's published work can only automate a small fraction of that expert's actual job.Their words
These would only automate about 15% of what I do as a performance engineer, and will go out of date if I'm not training it to follow industry changes.
21 November 2025
From one piece Intel is listening, don't waste your shot 2 beliefs, in the piece's order there
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Their words
It isn't easy dealing with peer pressure and a room of warm and friendly staff begging you say something, anything nice about their terrible product for fear of losing their jobs -- and realizing you must be brutal to their faces otherwise you're not helping the vendor or your own company.
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Their words
If you are in regular meetings with a hardware vendor as a customer (or potential customer) you can accomplish a lot by providing firm and tough feedback, particularly with Intel today.
16 November 2025
From one piece Third Stage Engineering 2 beliefs, in the piece's order there
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korrents.com
Fair hardware benchmarks must use the best software and tuning for each hardware option, not hardware specs alone.Their words
The most accurate and realistic evaluation for HW involves selecting the best software and then tuning it, and doing this for all HW options.
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korrents.com
Computer hardware performance depends on hardware, software, and tuning together, not hardware alone.Their words
You need all three stages to reach the highest, and most competitive, performance.
4 August 2025
3 August 2025
From one piece When to Hire a Computer Performance Engineering Team (2025) part 1 of 2 3 beliefs, in the piece's order there
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korrents.com
A performance test without an explanation of its limiting factor should be treated as unanalyzed and possibly bogus.Their words
Any performance test should be accompanied by an explanation of the limiting factor, since no explanation will reveal the test wasn't analyzed and the result may be bogus.
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korrents.com
Monitoring tools that do periodic work can themselves cause the latency outliers they were installed to diagnose.Their words
One performance anti-pattern is when a company, to debug one performance problem, installs a monitoring tool that periodically does work and causes application latency outliers.
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Their words
A new performance team can likely find enough optimizations to halve infrastructure spend in their first couple of years, even for companies that have been using commercial performance or observability tools.
14 July 2025
24 May 2025
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Recommendstheir ownrcmnd.app
Systems Performance, 2nd editionTheir words
Systems Performance 2nd edition - Brendan Gregg (Addison-Wesley, 2021)
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Recommendstheir ownrcmnd.app
BPF Performance ToolsTheir words
BPF Performance Tools - Brendan Gregg (Addison-Wesley, 2019)
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Recommendsaffiliate linkrcmnd.app
The Art of Capacity PlanningTheir words
The Art of Capacity Planning - John Allspaw (O'Reilly, 2008)
+ 19 more
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Recommendsaffiliate linkrcmnd.app
The Practical Performance AnalystTheir words
The Practical Performance Analyst - Neil Gunther (McGraw Hill, 1997)
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Recommendsaffiliate linkrcmnd.app
Linux Kernel Development, 3rd Ed.Their words
Linux Kernel Development, 3rd Ed. - Robert Love (Addison-Wesley, 2010)
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Recommendsaffiliate linkrcmnd.app
Understanding the Linux Kernel, 3rd Ed.Their words
Understanding the Linux Kernel, 3rd Ed. - Daniel P. Bovet, Marco Cesati Ph.D. (O'Reilly, 2005)
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Recommendsaffiliate linkrcmnd.app
The Design of the Unix Operating SystemTheir words
The Design of the Unix Operating System - Maurice J. Bach (Prentice Hall, 1986)
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Recommendsaffiliate linkrcmnd.app
The Cuckoo's EggTheir words
The Cuckoo's Egg - Cliff Stoll (Gallery, 2005)
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Recommendsaffiliate linkrcmnd.app
CryptonomiconTheir words
Cryptonomicon - Neal Stephenson
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Recommendsaffiliate linkrcmnd.app
Applied CryptographyTheir words
Applied Cryptography - Bruce Schneier (Wiley, 1996)
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Recommendsaffiliate linkrcmnd.app
The Art of Unix ProgrammingTheir words
The Art of Unix Programming - Eric S. Raymond (Addison-Wesley, 2003)
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Recommendsrcmnd.app
The Practice of ProgrammingTheir words
The Practice of Programming - Brian Kernighan, Rob Pike (Addison-Wesley, 1999)
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Recommendsaffiliate linkrcmnd.app
The Mythical Man-MonthTheir words
The Mythical Man-Month - Frederick P. Brooks (Addison-Wesley, 1995/1975)
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Recommendsaffiliate linkrcmnd.app
Expert C ProgrammingTheir words
Expert C Programming - Peter van der Linden (Prentice Hall, 1994)
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Recommendsaffiliate linkrcmnd.app
The C Programming Language, 2nd Ed.Their words
The C Programming Language 2nd Ed. - Brian W. Kernighan, Dennis M. Ritchie (Prentice Hall, 1988)
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Recommendsaffiliate linkrcmnd.app
The AWK Programming LanguageTheir words
The AWK Programming Language - Alfred V. Aho, Brian W. Kernighan, Peter J. Weinberger (Addison Wesley, 1988)
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Recommendsrcmnd.app
UNIX: A History and a MemoirTheir words
UNIX: A History and a Memoir - Brian W Kernighan (independent, 2019)
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Recommendsaffiliate linkrcmnd.app
Just For FunTheir words
Just For Fun - Linus Torvalds (Harper, 2002)
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Recommendsaffiliate linkrcmnd.app
Where Wizards Stay Up LateTheir words
Where Wizards Stay Up Late - Katie Hafner, Matthew Lyon (Simon & Schuster, 1998)
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Recommendsaffiliate linkrcmnd.app
Skunk WorksTheir words
Skunk Works - Ben R. Rich & Leo Janos (Black Bay Books, 1996)
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Recommendsaffiliate linkrcmnd.app
The Worst Journey in the WorldTheir words
The Worst Journey in the World - Apsley Cherry-Garrard (Penguin, 2006/1922)
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Recommendsaffiliate linkrcmnd.app
The No Asshole RuleTheir words
The No Asshole Rule - Robert I. Sutton (Business Plus, 2010)
22 May 2025
21 May 2025
From one piece 3 Years of Extremely Remote Work 2 beliefs, in the piece's order there
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korrents.com
Giving local staff authority over more-qualified remote workers reduces a company's competitivenessTheir words
there's a power imbalance: the local worker is in charge and doesn't have to listen. This reduces company competitiveness.
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korrents.com
Remote workers are often passed over for opportunities in favor of less-qualified local colleaguesTheir words
Opportunities can be given to local workers despite the remote worker being more qualified, or even number one in the world in that area.
30 April 2025
From one piece Doom GPU Flame Graphs 2 beliefs, in the piece's order there
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korrents.com
Major Linux distributions are increasingly shipping system libraries with frame pointers enabled by defaultTheir words
This is getting easier in the lastest versions of Fedora and Ubuntu (e.g., Ubuntu 24.04 LTS) which are shipping system libraries with frame pointers by default.
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korrents.com
NVIDIA's Nsight Graphics GPU flame graphs are shallow and cumbersome to use compared to full-stack profiling toolsTheir words
They do have flame graphs in Nsight Graphics for GPU workloads, although their flame graphs are currently shallow as it is GPU code only, and onerous to use as I believe it requires an interposer; on the plus side they have click-to-source.
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