http://shootout.alioth.debian.org/u32/benchmark.php?test=all... <- That still looks sort of far to me.
>> 3. Running dynamic languages on Mono is slow. Look at the speed of all the dynamic languages on Mono (or the JVM for that matter), and compare them to native implementations of dynamic languages, in particular JavaScript and Lua. The native implementations beat dynamic languages on Mono by a large margin, simply because .NET is a bytecode made for static languages.
It's not fair to compare JavaScript, which is already approaching a limit of how fast it can go, with the speed it gets running in Mono. Why? The two implementations have a vast difference of amount of energy and resources thrown at them; had Google, Mozilla, and Microsoft wanted JS to run fast on Mono, it would run fast on Mono.
Also saying that .NET is a bytecode made for static languages is kind of iffy now that the "Dynamic Language Runtime" is a part of .NET
2. It is true that JS on Mono has had far less work done, and that the DLR exists. However, the fact remains that dynamic languages are a late addition to the JVM/.NET model. For example, one very important thing for dynamic language performance is PICs, and to my knowledge there is no good example of fast PIC performance on the JVM or CLR. In fact, we don't even have a good example of a generic virtual machine that can run multiple dynamic languages fast (Parrot exists, but is not that fast) - all the fast dynamic language implementations are language-specific, so it shouldn't surprise us that VMs built for static languages don't do that well either.
Outside the browser you probably have a little more freedom, but it's not like you get to pick and chose in the style of "Oh, I'll execute this function in V8 since it does this faster, and that function in SpiderMonkey since it's faster there". For this reason, I don't think the fact Alioth only has measures for one engine would make a significant difference in the overall comparison. You'd be, for the most part, gaining performance in one place by sacrificing in another.
Anyway, in my personal experience, I've ran into performance problems in JS a lot more often than with C#. I also have to go through a lot more tedious practices to ensure my JS code runs as fast as it can, where as in C# Some.lookup.with.lots.of.dots.does.not.scare.me(). That's why your claim sort of surprised me. Then again, the last serious JS performance problem I had was 6 months ago (before FF4), so maybe a lot has happened in those 6 months.
By the way, I'm not too informed on how type inference is done in SpiderMonkey, so I may be completely wrong in mentioning this, but it sounds like they're trying to speed up a dynamic language by mimicking static typing. If that's how far they're going to improve performance, maybe soon enough JavaScript will in fact sit better in the Mono/.NET/JVM?
About the last 6 months: Yes, a lot happened during that time, namely FF4's JaegerMonkey and Chrome's Crankshaft. Both are significant improvements.
About typing, yes, in a way that could let this code run faster inside the JVM or Mono. If you can figure out the types, you can generate fast statically typed code for those VMs. However, type analysis can be both static and dynamic, should integrate with the PICs and so forth. So even with that, I don't expect dynamic languages to be able to run very fast on static language VMs.
1) Always read the program source code!
Why the performance difference between the C# Mono #2 program
http://shootout.alioth.debian.org/u32/program.php?test=pidig...
and the C# Mono #3 program?
http://shootout.alioth.debian.org/u32/program.php?test=pidig...
2) Always read the program source code!
Why the fast fast fast V8 regex-dna performance?
http://shootout.alioth.debian.org/u32/program.php?test=regex...
They raced up, and down, and around and around and around, and forwards and backwards and sideways and upside-down.
Cheetah's friends said "it's not fair" - everyone knows Cheetah is the fastest creature but the races are too long and Cheetah gets tired!
Falcon's friends said "it's not fair" - everyone knows Falcon is the fastest creature but Falcon doesn't walk very well, he soars across the sky!
Horse's friends said "it's not fair" - everyone knows Horse is the fastest creature but this is only a yearling, you must stop the races until a stallion takes part!
Man's friends said "it's not fair" - everyone knows that in the "real world" Man would use a motorbike, you must wait until Man has fueled and warmed up the engine!
Snail's friends said "it's not fair" - everyone knows that a creature should leave a slime trail, all those other creatures are cheating!
Dalmatian's tail was banging on the ground. Dalmatian panted and between breaths said "Look at that beautiful mountain, let's race to the top!"
Do you have data to back this up? At least SpiderMonkey has projects in the works that give significant speedups on various workloads already, and lots of headroom left...
I would not be surprised to see another factor of 5 or so speedups on various code in the next few years in JS implementations.
Yeah I know, it's not a proper citation, I tried to find where exactly that was said at Google IO but found nothing so far. Either way, I didn't question it at the time I read it because given how dynamic JavaScript is I'd imagine there's only so much you can do to speed it up. Then again, this was coming from Google, and for all anyone knows the cause might just be them focusing more on Native Client instead of V8 for apps that need performance.
It's unfortunate that Google is deciding to focus on Native Client, with its portability issues, if that's what's going on.
