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by FooBarWidget 3670 days ago
I was once involved in a large-scale government project that rewrote a Java app to RoR. They went from 50 servers to 10.

It has probably got more to do with the rewrite and the new architecture than whatever language it was written in.

2 comments

What? It absolutely has to do with the language.

Ruby binary trees: 57 seconds Scala binary trees: 11 seconds

[1] - http://benchmarksgame.alioth.debian.org/u64q/ruby.html [2] - http://benchmarksgame.alioth.debian.org/u64q/scala.html

That would mean something if Ruby apps are 100% Ruby and/or are performing binary tree operations all the time, or doing similar kinds of CPU-intensive operations as depicted in the alioth benchmarks. But they don't. Ruby web apps perform lots of string manipulation, memory allocation, I/O. A lot of expensive things are offloaded to C libraries. Things like XML parsing are offloaded to native libraries like libxml; nobody uses an XML parser fully implemented in Ruby. Ruby does not reimplemented gzip compression in Ruby, it uses zlib. So the alioth benchmarks are not representative of real-world performance.
>> Ruby web apps perform lots of string manipulation, memory allocation, I/O. <<

    string manipulation
http://benchmarksgame.alioth.debian.org/u64q/program.php?tes...

    memory allocation
http://benchmarksgame.alioth.debian.org/u64q/program.php?tes...

    I/O
fasta, fasta-redux, reverse-complement write 250MB

regex-dna reads 50MB; k-nucleotide, reverse-complement read 250MB

>> …offloaded to native libraries… So the alioth benchmarks are not representative of real-world performance. <<

The benchmarks game does show C programs ;-)

The benchmarks game does show scripting-languages explicitly using native libraries:

http://benchmarksgame.alioth.debian.org/u64q/program.php?tes...

> string manipulation

That benchmark performs string manipulations that rarely occur in web apps. Web apps need: concatenation, substring, find/replace, maybe with regexps. All of those are implemented in C.

> memory allocation

Web apps don't tend to implement entire trees in pure Ruby. That benchmark is completely non-representative of real-world performance.

What exactly are you getting at? Of course it's easy to find a bunch of synthetic benchmarks that show weaknesses in particular cases. Still doesn't prove anything.

> Web apps need: concatenation, substring, find/replace, maybe with regexps. All of those are implemented in C.

join and gsub?

http://benchmarksgame.alioth.debian.org/u64q/program.php?tes...

> Web apps don't tend to implement entire trees in pure Ruby.

Nor do other apps but that is what Hans Boehm came up with as a simple GC benchmark.

http://hboehm.info/gc/gc_bench/

> What exactly are you getting at?

You don't seem to know what is shown on the benchmarks game website.

Doesn't your regex-dna benchmark kind of prove my point? Just look at the comparisons here: http://benchmarksgame.alioth.debian.org/u64q/performance.php...

C GCC: 2.46 sec

Java: 8.23 sec

Ruby #8: 9.35 sec

It's only about 4x slower than pure C in this case, and only a little slower than Java which has a very good JIT.

> You don't seem to know what is shown on the benchmarks game website.

How funny of you to say that while acting as if the benchmarks "prove" Ruby is the ultimate spawn of the devil that eats away any and all performance. The website itself tells you not to jump to conclusions and that the app itself is the ultimate benchmark: http://benchmarksgame.alioth.debian.org/dont-jump-to-conclus...

Or the fact that new servers are an order of magnitude faster than the ones they replaced.
Order of magnitude faster? I doubt that. Unless the old ones were really old / slow to begin with. But really, we are both speculating without knowing the facts.