4 ms·

If it's straightforward to get near-C performance out of those languages, why do they lose out so badly in the language shootout? eg: Tracemonkey vs Java - h

by zmimon 17y ago

If it's straightforward to get near-C performance out of those languages, why do they lose out so badly in the language shootout? eg: Tracemonkey vs Java - http://shootout.alioth.debian.org/u32q/benchmark.php?test=all&lang=javasteady&lang2=tracemonkey&box=1 http://shootout.alioth.debian.org/u32q/benchmark.php?test=al... Java varies between 10 and 100 times as fast as Tracemonkey in all the tests. If you think it is straightforward to write code that equals C performance, you should do so and submit it to the shootout to prove your point. Personally, I don't believe you can :-)

heyadayo 17y ago
Looks like someone took you up, and beat C with javascript: http://shootout.alioth.debian.org/u32/benchmark.php?test=regexdna&lang=all http://shootout.alioth.debian.org/u32/benchmark.php?test=reg...
blub 17y ago
It's straightforward because talk is cheap. Maybe jrockway could write some near-C speed Python or JavaScript code to enlighten us. And by near-C speed I don't mean 20% slower...
- berntb 17y ago
  I assume he was thinking of an area like web programming, where a DB mostly is the practical limiting factor for speed. (Or rewriting the (often small) speed critical parts in C, after benchmarking.)
  - jrockway 17y ago
    No, I wasn't. I was talking about the speed-critical tight loops. Once you let GHC or TraceMonkey or PyPy or ... know what the machine types of your data is, they will generate very fast code; often the same instructions that the C compiler would generate. C is fast because the programmer explicitly names the machine types to be used. Other languages are slow because their operations can't always be expressed in terms of operations the machine can do. (Consider Perl and "2 + 2". This is "slow" because 2 is a "SV", and that means before anything can happen, the integer 2 has to be unboxed from the SV, the runtime has to decide which "+" to use, and then the result has to be boxed in a "SV". This is much slower than running the "ADD" instruction. But if you can somehow specify, "this is not a special boxed value, just treat it as a machine integer and don't worry about overflow or anything special", then you are doing the same thing as C. Modern VMs (and static compilers) can guess this for you and generate the right code.)

by zmimon 17y ago

heyadayo 17y ago

Looks like someone took you up, and beat C with javascript: http://shootout.alioth.debian.org/u32/benchmark.php?test=regexdna&lang=all http://shootout.alioth.debian.org/u32/benchmark.php?test=reg...

blub 17y ago

It's straightforward because talk is cheap. Maybe jrockway could write some near-C speed Python or JavaScript code to enlighten us. And by near-C speed I don't mean 20% slower...

berntb 17y ago
I assume he was thinking of an area like web programming, where a DB mostly is the practical limiting factor for speed. (Or rewriting the (often small) speed critical parts in C, after benchmarking.)
- jrockway 17y ago
  No, I wasn't. I was talking about the speed-critical tight loops. Once you let GHC or TraceMonkey or PyPy or ... know what the machine types of your data is, they will generate very fast code; often the same instructions that the C compiler would generate. C is fast because the programmer explicitly names the machine types to be used. Other languages are slow because their operations can't always be expressed in terms of operations the machine can do. (Consider Perl and "2 + 2". This is "slow" because 2 is a "SV", and that means before anything can happen, the integer 2 has to be unboxed from the SV, the runtime has to decide which "+" to use, and then the result has to be boxed in a "SV". This is much slower than running the "ADD" instruction. But if you can somehow specify, "this is not a special boxed value, just treat it as a machine integer and don't worry about overflow or anything special", then you are doing the same thing as C. Modern VMs (and static compilers) can guess this for you and generate the right code.)