Energy Efficiency Across Programming Languages
sites.google.com
sites.google.com
1. Pascal, surprisingly, the most memory efficient of all. I should take a look at the implementation they used.
2. Rust a good alternative to C which leads in "energy efficiency" and speed.
3. Common Lisp most energy-efficient and fastest and smallest memory footprint of all the dynamic programming languages in the list -- like Python, Ruby, Lua, Perl, and even Racket (which fares pretty well)
4. PHP, JRuby, Ruby, Typescript, Perl, Python, being massively slow than the fastest languages, for example Ruby being 59 times slower than Rust or C.
I agree that these languages (in item 4) are "acceptably fast" for many applications, but we can't say they are "close to the speed" of the fastest languages, even more if we consider the fastest dynamic+interactive languages like Lisp (Python being 21 times slower than Lisp.)
5. I wonder which implementation of Lua they used. Lua can be pretty fast, one of the fastest dynamic languages out there.
Pascal is a "hidden" gem in the area of languages. Sadly not enough pus for it, but imagine if it have the push that other languages have...
(Have implementation in pascal!)
I agree. Programmers won't look at it because they perceive it to be old and out-of-date. But the language hasn't stood still. It's a fast, low-memory language. FreePascal with the Lazarus IDE is one of the best cross-platform development toolkits for building native desktop apps.
Sadly a lot of programmers can never see beyond the verbose (but readable) syntax.
http://www.elementscompiler.com/elements/oxygene/
Exist various dialects of pascal (Modula, Oberon, etc) so is not something so far in the wind.
But if you lose too much of the syntax you remove part of the charm.
Failing that there is always Ada, .NET Native, Kotlin Native, D,...
Pascal and C give the programmer basically the same control over memory layout, no?
The way methods are attached to types appeared first in Oberon-2.
Type assertions are similar to Oberon.
The unsafe package idea is similar to SYSTEM in Oberon or Pascal.
The stronger type semantics forcing explicit casts.
Don't mean to assume you are wrong, but what are you referring to?
I looked at the binary trees benchmark and while the Python version used multiprocessing to parallelize the code, the Lua version was not parallelized at all..
.. not that this is entirely unrealistic. Python comes with MP in the standard library while I am not aware of any "industrial strength" solution for Lua, whether MP or thread-based.
http://benchmarksgame.alioth.debian.org/u64q/program.php?tes...
The choice of 5.3 is pretty strange, as Lua is known to split in two at 5.2, because LuaJIT was fixed to 5.1 variant with compat backports and is to my opinion an "industrial" Lua standard. 5.x are actually three different (but not absolutely superior to each other) languages with shared 5-like foundation and app-level code compatibility, so speaking about Lua in general is pointless in a sense.
There is a table with the versions they used¹, but they don't mention the implementation – in can be inferred for some: e.g. for Pascal they used the Free Pascal Compiler.
① - https://sites.google.com/view/energy-efficiency-languages/se...
LuaJIT is at least an order of magnitude(10x) faster.
I'd be interested in seeing how it fared; Lua really is a nice language.
Take a look at some of the TypeScript code and compare it to the Javascript versions. At least some are way different, i.e. the TypeScript uses "modern" JS features and the JS version... looks about as much like C as it can.
I can see comparing different target versions of Javascript against one another (es2015 vs es2017 for instance), but it all depends on the VM chosen as well.
Apparently 5.3, but I am very skeptical of these results. Also the way the data is organised is very weird. One should not compare a JIT compiled VM (JavaScript) with interpreters (Lua, Python, Ruby...). An honest approach would have used LuaJIT, PyPy etc. or separated the languages into "families" better. Not to mention the choice of algorithms they used. Some of the algorithms in the benchmark game have many flaws.
As it was already stated in this thread, some of the Python ones were multithreaded but the ones in Lua weren't. Why? In a different benchmark I've seen algorithms using C wrappers for Python, but not in Lua. While I understand wrapping C and multithreading reflect the industry use in Python, so they do in Lua. Benchmarks are useless if you are not consistent in the implementations of the things you are comparing with. It disgusts me, to be honest, when I see benchmarks comparing JIT compilers with vanilla Lua just to say "hey we're faster", as LuaJIT does not even exist. It looks like pure dishonesty. In the case of this paper in particular, as they do not represent any language, it strikes me as lack of research / understanding.
No mystery: someone has made the effort to contribute all those multi-process Python programs; no one has made the effort to contribute all those multi-process Lua programs.
If someone who didn't know Lua wrote those programs, then you'd complain that the programs weren't written by an expert.
If Lua wasn't included then I think you'd complain about that too.
I happened to spot a problem on this one on the Lua part and also on some other parts concerning how they classify things, because it happens to be things I know more. I'm not going out of my way to look for problems in the rest of the paper because I'm not a reviewer and I have better things to do.
But if I was the one way conducting this academic research, then I would want the results not to be bogus. The difference here is this is not a blog post about some bullshit comparison someone is making. If that was the case, then alright, if public contributed algorithms failed to represent exactly what was being looked for, why not go for whatever is out there. I just expect a more rigorous procedure from academics.
Are they likely to be expert in all those programming languages?
----
If Lua wasn't included would you complain ?
( Like this:
https://news.ycombinator.com/item?id=15255427
https://news.ycombinator.com/item?id=15251242
https://news.ycombinator.com/item?id=15251144
)
No, but again, I take paper results very seriously. Misleading results are bad for science, period. Here is an example of more rigorous research: https://arxiv.org/pdf/1602.00602.pdf
> If Lua wasn't included would you complain ?
Maybe I would, who knows. I did also mention in another comment it would be nice if Julia was there. It depends how relevant they are for the research being conducted. As a language used very often in microcontrollers, Lua is very relevant for energy efficiency research. I don't know anything about Forth, but I wouldn't just dismiss people saying it should be there with "then contribute forth algorithms to the benchmarks game yourself".
"disgusts me" & "pure dishonesty" don't seem like a serious response.
> … an example of more rigorous research…
Which again uses programs that were contributed to the benchmarks game.
> … wouldn't just dismiss people…
I wouldn't just dismiss them: I'd tell them that others have every right to present what seems important to them, and exclude what seems less important -- without being accused of dishonesty.
There's only so-much time & money.
Because ?
Why should "different families" of language implementation not be compared?
Secondly, why would you compare the performance of C and Ruby, for example? Ruby is bound to be slower for design reasons. Doing it to say "Look, C is fast!" doesn't mean anything. There are different reasons one would compare C and Rust, or C and Ruby. The way the results are displayed and what it tries to convey is very important.
If you're not making a baseline, or being very clear, etc. then it's just misleading to have a benchmark portraying Javascript as faster than Ruby, Python and Lua. Either you put those into their correct classifications clearly, or you compare it with LuaJIT, PyPy, Julia etc.
The paper, both shows tables that include all the results (ordered by Energy consumed) and shows separate charts for what the authors classify as "either a compiled, interpreted, or virtual-machine language".
What is "an interpreted language" ?
"Although we refer to Lua as an interpreted language, Lua always precompiles source code to an intermediate form before running it. … The presence of a compilation phase may sound out of place in an interpreted language like Lua. However, the distinguishing feature of interpreted languages is not that they are not compiled, but that any eventual compiler is part of the language runtime and that, therefore, it is possible (and easy) to execute code generated on the fly."
p57 "Programming in Lua" (2003)
> … why would you compare the performance of C and Ruby, for example? Ruby is bound to be slower…
Except when the C program is measured to be 50x slower than the Ruby program --
http://benchmarksgame.alioth.debian.org/u32/compare.php?lang...
I guess you misinterpreted my comment. I didn't imply there are no reasons to compare C and Ruby. I said the reason is important and the way you portray that, and the way you portray your results, changes things.
Do you think Roberto Ierusalimschy is confused about that ?
Again, here's what the creator of Lua says -- "… the distinguishing feature of interpreted languages is not that they are not compiled, but that any eventual compiler is part of the language runtime…"
EDIT:
Is that not what you mean by "interpreted language" ?
No, of course not. I think you are. You are clearly misinterpreting his words. I will repeat, (PUC)Lua is not compiled to machine code, but to an intermediate bytecode form. Those are completely different things, and what I said does not come in conflict at all with the quote you took from PiL, so I don't know what you are confronting me about.
Correct.
Now look at what Roberto Ierusalimschy means by "interpreted language": "… the distinguishing feature of interpreted languages is not that they are not compiled, but that any eventual compiler is part of the language runtime and that, therefore, it is possible (and easy) to execute code generated on the fly."
Is that what you mean by "interpreted language" ?
That's a very definite claim, for which you provide no supporting evidence ;-)
- It would be weird to expect programs specifically optimized for a performance benchmark, to also be optimal for energy usage or memory. Maybe less weird for energy, if runtime is the biggest factor in how much energy gets used. But I'd expect there to be huge tradeoffs between runtime and memory usage, once we start really optimizing for memory.
- Running the Benchmarks Game has meant doing a lot of work to figure out what the relationship between "optimal" and "representative" is, and what the rules of the game should be as a result. Even if we take it for granted that we've answered those questions in a way that gives us useful benchmarks for performance, it would be weird to expect the answers to be exactly the same in benchmarks for energy or memory.
This will almost always also be the most energy efficient thing on modern cpus.
It will not always be the most memory efficient way. I neither agree or disagree with what they are measuring, its just data. I would not look at this if I was trying to get an idea of what languages are most memory efficient, maybe.
1. It features an atypically high allocation rate compared to real-world programs.
2. As a synthetic micro benchmark that only ever allocates objects of one size, it makes pool allocators look disproportionately good. But in real-world applications with varying object sizes, overuse of pool allocators creates a serious risk for fragmentation.
3. The rules allow programs that use manual memory management to use pretty much any pool allocator library that they can get their hands on, but forbid garbage-collected languages from adjusting their GC parameters (last I checked, you could easily improve the performance of OCaml and Dart for that benchmark by a factor of 2-3 simply by adjusting GC settings, especially the size of the minor heap).
And still there's outrage that programs with allocators custom-written for binary-trees are rejected :-)
Do you have any supporting evidence for this? Real-world programs can be pretty allocation heavy, and if anything high allocation rates would "unfairly" benefit GC languages since native programs are banned from using arena allocators.
> As a synthetic micro benchmark that only ever allocates objects of one size, it makes pool allocators look disproportionately good. But in real-world applications with varying object size, overuse of pool allocators is a serious risk for fragmentation.
Huh? It's so incredibly common in the real-world for a structure to be of a single type that pretty much every language makes that first-class supported via templates.
And since they are single-size there's no risk of fragmentation at all. Indeed object pools are typically how you avoid fragmentation, they are not things that cause it. So I'm not sure what you're trying to get at with that comment.
> The rules allow programs that use manual memory management to use pretty much any pool allocator library that they can get their hand on, but forbid garbage-collected languages from adjusting their GC parameters (last I checked, you could easily improve the performance of OCaml and Dart for that benchmark by a factor of 2-3 simply by adjusting GC settings, especially the size of the nursery).
Last I checked if I write a Dart library I can't adjust the GC settings in my library to make my library run better, either, but if I ship a C++ library I can absolutely use a pool allocator to make my library run better (and indeed this is exactly what real libraries do)
So I'd call this a good rule, and allowing tweaking of GC parameters would be more about trying to over-tune the runtime to the benchmark rather than the benchmark illustrating what is feasible to achieve in the language as a library or as part of a larger system.
For starters, by virtue of the construction of the benchmark alone, which mostly is about stress-testing allocation.
There are also quite a few papers that benchmark allocators, such as [1], where you can see that such allocation rates aren't exactly ordinary.
> Real-world programs can be pretty allocation heavy,
I said "atypical", not "impossible". Obviously, I can construct real-world programs with pretty much arbitrary allocation rates, but especially performance-sensitive code will avoid that, if only because it hurts memory locality.
> and if anything high allocation rates would "unfairly" benefit GC languages since native programs are banned from using arena allocators.
My point is that this apples vs. oranges, no matter how you cut it. I don't want one side to "win", I want results that are good science.
> Huh? It's so incredibly common in the real-world for a structure to be of a single type that pretty much every language makes that first-class supported via templates.
That sentence doesn't make sense, unless you live in a world where C++ is the only programming language (because templates are pretty much C++-specific).
> And since they are single-size there's no risk of fragmentation at all.
Simple example: A program alternates between allocating objects of size N (and then freeing most, but not all of them) and allocating objects of size M (and then freeing most, but not all of them). Worst case means that one object per block is enough to keep an entire block alive.
The concern here is long-running programs: if you have high allocation rates, you also have frequent deallocations (or the program eventually stops allocating).
> Last I checked if I write a Dart library I can't adjust the GC settings in my library to make my library run better, either, but if I ship a C++ library I can absolutely use a pool allocator to make my library run better (and indeed this is exactly what real libraries do)
And instead you could tune the final application; allocation tuning is often a non-local concern. Apples and oranges again.
Importantly, you seem to be mistaking this for a tribal argument (the GC tribe vs. the manual memory management tribe), whereas my point is simply that the benchmark is bad and tries to compare incomparable things.
That's not actually true at all. Games, for example, can have high allocation rates. But they use custom allocators to make those allocations extremely cheap using things like arena allocators for the allocations for a frame.
> My point is that this apples vs. oranges, no matter how you cut it.
It's not apples vs. oranges at all, though. It's "how can you solve this problem in the optimal way on any given language"
The set of rules does not appear to unfairly punish any particular language design. You can do object pools in GC'd languages, too, for example.
Does the problem itself have bias? Probably, but real problems in the real world have inherent language biases, too. That's a problem with reality, not a problem with the benchmark.
> That sentence doesn't make sense, unless you live in a world where C++ is the only programming language (because templates are pretty much C++-specific).
generics? Not C++ specific.
> Simple example: A program alternates between allocating objects of size N (and then freeing most, but not all of them) and allocating objects of size M (and then freeing most, but not all of them). Worst case means that one object per block is enough to keep an entire block alive.
That example results in terrible fragmentation for everyone if M > N other than a compacting GC. It's not made particularly worse by an object pool.
> Importantly, you seem to be mistaking this for a tribal argument (the GC tribe vs. the manual memory management tribe), whereas my point is simply that the benchmark is bad and tries to compare incomparable things.
I'm not mistaking it for that at all. I'm saying your arguments for why it's bad are bad. You seem to be upset that benchmarks for problems exist that do not represent your priorities of what should be benchmarked.
Actually the rules for the Computer Language Benchmarks Game say about Binary Tree: 'As a practical matter, the myriad ways to custom allocate memory will not be accepted. Please don't implement your own custom "arena" or "memory pool" or "free list" - they will not be accepted.'
And for any synthetic microbenchmark, that's unlikely to reflect real-world workloads, as they tend to narrowly test just one aspect of the language (or rather, its implementation).
Remember, we're talking about a peer-reviewed paper here, where the burden to show relevance is upon the authors. Section 4 ("Threats to Validity") of the paper does not really address that adequately.
As the Computer Language Benchmark Game site itself quotes (and one reason why it calls itself a "game" and disavows usefulness for actual programming language comparisons):
Attempts at running programs that are much simpler than a real
application have led to performance pitfalls. Examples include:
...
* Toy programs, which are 100-line programs from beginning
programming assignments ...
* Synthetic benchmarks, which are small, fake programs invented
to try to match the profile and behavior of real applications
...
All three are discredited today, usually because the compiler
writer and architect can conspire to make the computer appear
faster on these stand-in programs than on real applications.
> You can do object pools in GC'd languages, too, for example.
No. The rules do not allow for that. I did mention how arbitrary they are, right? The regex-redux benchmark, for example, comes down to what the best external library is that you can link to under the rules. The gcc version wins in large part (being massively better than the g++ version, which relies on Boost regexes) because it uses the JIT version of libpcre. It's borderline absurd.
> generics? Not C++ specific.
You said templates, not generics. Generics alone are not necessarily sufficient to implement pool allocators. Plus, C++ is the only language that has major adoption that has both some form of generics and manual memory management.
> That example results in terrible fragmentation for everyone if M > N other than a compacting GC. It's not made particularly worse by an object pool.
This is false. Even a simple first-fit allocator can fare better, for example. Obviously, a compacting GC can avoid external fragmentation (almost) entirely, no matter the cause.
No: http://benchmarksgame.alioth.debian.org/sometimes-people-jus...
> … and disavows usefulness for actual programming language comparisons…
Not a definitive conclusion but a starting point.
That trump card wasn't actually mentioned in your original comment.
The difficulty is that programming languages (and programming language implementations) are more different than apples and oranges, but the question is still asked - "Will my program be faster if I write it in language X?" - and there's still a wish for a simpler answer than - It depends how you write it!
http://benchmarksgame.alioth.debian.org/dont-jump-to-conclus...
The code guidelines in their benchmarks represent real programming practices in those languages. They promote "idiomatic" code because it is meant to represent the typical quality of code in the real world. Obviously many of the examples could be made more performant, but in doing so you would made the code less representative of the real world. Example: the typescript code outputs wanky ES6 features that are slower than their old plain js counterparts (classes, arrow functions, let, etc). You could abuse the ts code until its output is identical to js, but you would have a pointless benchmark now.
What would the benchmark honestly represent if the code looked nothing like code in the real world? The theoretical speed of the language just doesn't matter.
In fact, JS engines have been optimizing their performance around numerical benchmarks for decades. The benchmark problems (nbody, etc) are actually highly unrepresentative of real javascript performance because real world javascript is touching strings and awful DOM apis and messing with dictionaries all day.
Your 'real-world workload' should be stuff like text editor operations, a domain where JS's alleged 6x slowdown compared to C has not been remotely approached by current editors.
This could not be further from my observations when I tried contributing. These results are neither controlled nor the result of idiomatic programs.
Perhaps idiomatic was the wrong word. I mean that the code isn't supposed to be fighting the language.
What were your observations when you were contributing? Which problems were you working on? Any chance you still have the code?
That's the issue: those programs that did best were those that fought the language the most, and those that pushed the closest to the edge of the rules. You can't, in general, look at two programs and assume they approach the problem the same way.
Then factor in the energy of the developer and its supporting environment for the extra development time (commuting, air conditioning / heating, laptop, monitors, etc.) The less the load on the app, the more important it gets.
No, it's almost always negligible because it's essentially a one-time cost, whereas the program's inefficiencies are multiplied by an unknown number of users over an unknown period of time (cf. Cobol programs still being in use today) - but for sure your goal is often to maximize both of these unknown numbers.
This fact is very obvious when you develop hardware/firmware combos. The firmware is often designed to minimize the hardware costs (RAM size, mass storage size,...) because the cost of producing the hardware is per piece, while the development cost is mostly a one-time cost that one rarely includes in the total cost of the product.
But perhaps archive your code elsewhere. Github? Lots of language communities participated in past versions of the game. Like gforth and bigforth on shootout.alioth.debian.org circa 2008. Now it seems little remains but a few archive.org snapshots without source. Though perhaps all of that code was archived somewhere else that I'm not quickly finding?
Sitting in the same old-repo, a GForth binary-trees program from 2005 --
https://alioth.debian.org/scm/viewvc.php/shootout/bench/bina...
edit Now it seems little remains but for you to lift-that-shade and tell-everyone how amazing it is that someone took the trouble to archive those obscure old programs.
Unlike the old shootout, adding languages directly to benchmarksgame.alioth.debian.org is not an option. "Because I know it will take more time than I choose. Been there; done that."[2] :) Instead, the code is available[3], and communities are invited to document their own benchmarksgame comparisons[2], such as Nim''s[4]. The OP used different code[5].
A brief glance at the current benchmarks, suggests there is some overlap with the old ones. Or at least an overlap of names - the requirements may have changed. So it might be possible to get started fairly easily? Perhaps even to do several languages...
[1] https://alioth.debian.org/scm/viewvc.php/shootout/bench/?roo... [2] https://benchmarksgame.alioth.debian.org/play.html [3] https://github.com/Byron/benchmarksgame-cvs-mirror [4] https://github.com/def-/nim-benchmarksgame [5] https://github.com/greensoftwarelab/Energy-Languages
The data would be crufty, of limited comparability. But combining easily browsable links to colorized source code, with "just for a rough feel" speed relative to C, might be sufficient for the use case of raising language awareness - "What is this C-speed-like language I've never heard of? Oh, that looks pretty! I think I'll explore this language's web page..."
Or alternately, use the language files on github to create a new, broader benchmarksgame. That is, distribute the work of benchmark revisions and makefile compiler options, but keep the testing centralized. I've no idea of the relative costs of those tasks, or of others. But a continuous integration shootout sounds intriguing.
It would be wonderful but how do you ensure any form of hardware consistency?
No, not unlike the old shootout -- exactly like it !
Please stop making things up.
Most of which were replaced by something better.
https://www.infoq.com/presentations/power-144-chip
As for efficiency, he mentions 7 picojoules per instruction in his forth chips.
I'm also kinda surprised that OCaml scored that high, considering how high-level it is.
You could say the opposite about Go.
The following blogspot explains how the author improved C# implementations after seeing defavorable C# results.
https://anthonylloyd.github.io/blog/2017/08/15/dotnetcore-pe...
[0]- Done at Xerox PARC, DEC/Olivetti, ETHZ, Erlangen, MSR
But really, if they hurt, then they get hurt. There's only so many knobs you can turn and so many runs you can run before you have to assemble a table and submit your paper. They put all the code online so you can try it yourself.
That does seem to be the case with some-of the benchmarks game programs --
http://benchmarksgame.alioth.debian.org/sometimes-people-jus...
I cannot explain the difference and if this is indeed an error by the authors of the paper it casts a fairly big shadow on the reliability of the rest of the data.
This may also explain why JS is really fast in a couple of the examples. Those script likely do almost nothing but call some built-in function that does all its work in C (or C++, or whatever).
[EDIT] OK, if I'm reading these[1][2] files correctly, it has more to do with the the TS version being written in "modern" "idiomatic" "beautiful" JS with promises and crap, and the vanilla JS one being written in "ugly" "bad" old-school 90's-lookin' C-ish Javascript.
[1] https://github.com/greensoftwarelab/Energy-Languages/blob/ma...
[2] https://github.com/greensoftwarelab/Energy-Languages/blob/ma...
Moreover, the top 5 languages that need less energy and
time to execute the solutions are: C (57J, 2019ms), Rust (59J,
2103ms), C++ (77J, 3155ms), Ada (98J, 3740ms), and Java
(114J, 3821ms); of these, only Java is not compiled.
The PHP result is interesting; they used 7.x which is roughly twice as efficient as older (5.x) versions; PHP 7 was primarily a (successful) effort to improve performance. If you extrapolate the PHP result to the old version (multiply by 2) it's nearly as bad as Perl and among the slowest/most costly. That certainly corroborates Facebook's several PHP re-implementations.
Granted, I also think considering Java to be "not compiled" is a slight misrepresentation since it does get compiled to Java bytecode.