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Comment by jmspring | Hacker News Reader

Honest question for those who got received CS/Engineering degrees in the last 10 years, did Amdahl's Law come up?

I've seen programming courses go away from assembler/c/c++ over the years to Java and then scripting languages at a couple local schools.

I wonder if the history/theory side changed as well.

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I published a paper this year that used it directly and even proposed a modification of it to model job time for a distributed execution environment with a centralized master governing scheduling, task serialization, etc.

When you talk scale-out of any large system, or manycore whatever, Amdahl's law is absolutely fundamental, and when you hear someone say "perfect horizontal scalability," Amdahl's law governs when that will no longer be true.

People who do theory on distributed algorithms use it even if they don't realize it.

Amdahl's Law was taught in my Alma mater's "computer architecture" course. This course was primarily around CPU operation and law was specifically brought up in regards to instruction mixes and provided CPU execution units, but was then generalized.

This was the 2nd in a series of the four required courses "low level" courses (assembly programming, computer architecture, operating systems, compilers).

I am a systems software developer and Amdahl's Law is one of my standard interview questions.

A current undergrad and TA for CS courses at Cal (UC Berkeley) checking in here. The course I TA for, CS 61C Machine Structures (inst.eecs.berkeley.edu/~cs61c/) introduces the concept in our unit on parallelism. This is a required course for all undergraduate CS majors and is the third course in the introductory series.

Yes, I'm taking CS now and I saw it last semester in "Advanced Computer Architecture", a year-3 core module for CS and CE student in NTU, Singapore.

It showed up in the context of a grad school seminar. I was shocked no one mentioned such a fundamental concept during my undergrad or regular classes. I've used the "law" to make arguments professionally several times.

Amdahl's Law definitely came up in my undergrad CE/CS courses at USC. I'm not sure how you could teach a computer architecture or processor design class and not mention it.

And for what it's worth, we still covered C/C++ and assembly (MIPS + x86), in addition to Java.

I did a degree in High Performance Computing and Amdahl's Law came up there. It never came up back when I was working on my undergrad C.S degree, but I didn't finish my degree either, so maybe it would have eventually.

CS degree. Never heard of it. I graduated about 5 years ago.

Thanks. It's always interesting to see what people with comparable degrees encounter.

I'm not a CS/Eng person, rather an astrophysicist who spends a reasonable amount of my time working on simulations. Amdahl's law has been mentioned during lectures at week-long schools on numerical methods.

I finished undergrad 2 years ago.

It never really came up until I took the Parallel Computing course late into my degree.

An interesting blog post from Cleve @ TMW: http://blogs.mathworks.com/cleve/2013/11/12/the-intel-hyperc...

I did a masters of HPC in University of Edinburgh. Amdahl's Law was being mentioned from day 1.

For me it did, yes. I first saw Amdahl's Law in a parallel computing course. Many of my professors were of the old guard though, and they made sure we learned the fundamentals. I'm grateful for it.

I came across Amdahl's law repeatedly in my CS course. Interestingly, I also came across it when studying for a MBA, in the context of operations management and speeding up business processes.

EE degrees yes definitely. I wish CS students learnt it too. Every fancy language du jour eventually has to generate machine code after all.

Yes, I'm about to finish up my undergrad CS degree, and Amdahl's Law came up in at least three separate classes, most notably my computer architecture course and my operating systems course. Side note, we were assigned to read Soul of a New Machine and the Pentium Chronicles in the computer architecture course, and most everyone enjoyed the books.

Australian National University - was discussed extensively in our 4th year Parallel Systems course, but not really anywhere else. Might have scored a mention in our 2nd year core Concurrent and Distributed Systems class, but I wouldn't remember.

I'm just outside of this range as I graduated with a BS in CS back in 2004, but learned about it when I took a computer architecture class in 2002, and I still enjoy seeing examples of it in real life.

Only did a few CS courses but it did come up in both the freshman sequence of courses and again in the Intro to Computer Architecture course. It was most certainly still being taught at my Java school.

Yes, in Operating Systems and in a parallel programming course. And on a few other occasions it was described informally, don't remember if the name actually was mentioned then.

It comes up repeatedly in Computer Science and Computer Engineering coursework at University of Illinois. Assembly, C and C++ are unavoidable in both programs.

Definitely at CSULA. It's taught in OS, Multiprocessing in CS undergraduate, and in Multimedia and Networking in EE/CE at the grad level.

CS degree in Mackenzie - Brazil, the law was mentioned in Parallel Computing course. I took this class last year.

We have used C/C++ with MPI and OpenMP.

I graduated CS just a few months ago. It was mentioned a few times, thankfully! The concept encouraged me to think about parallelism more.

Finished my degree about a year ago. Amdahl's Law came up in two courses (one of them mandatory for first year students).

IN 2006 I saw it in my operating systems/architecture textbook (Bryant/O'Halloran)

It definitely came up in CMU's 15-418 Parallel Architecture class.

I went to Maryland and yeah it came up in the Concurrency course

Yes, Computer Architecture course for EE at UAEU.

I have a dissenting opinion: Amdahl's law is obvious and therefore it doesn't need to be explicitly taught.

I agree with your (apparently unpopular) opinion. I'd never heard of this as a named law before, but it's just a restatement of critical path analysis in a computing context.

> I agree with your (apparently unpopular) opinion. I'd never heard of this as a named law before, but it's just a restatement of critical path analysis in a computing context.

I suspect it's one of those things that seems obvious in hindsight or in the context of how computers work today. But when it was first discussed, it may not have been as obvious.

I understand it was used as a marketing punchline. Further, the gripe that systems wouldn't scale turned out to be a challenge rather than a death sentence.

For me, yes.

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