4 ms·

Performance and scalability are two different things. My favorite example is to think of performance as being like the speed limit, and scalability as the abil

Performance and scalability are two different things. My favorite example is to think of performance as being like the speed limit, and scalability as the ability to easily add more lanes to the road. Once there are enough vehicles on the road, it doesn't matter how high you set the speed limit, they'll still slow to a crawl. Now imagine if there was a trivial way to add more lanes to the road. Clojure has very nice concurrency mechanisms baked right into the language.

optimiz3 13y ago
This doesn't answer the author's question. We know the difference between performance and scalability. How does it perform compared to Java?
- saosebastiao 13y ago
  It is slower than java. It can approach Java with type annotations which aren't that hard to do. It is faster than any other dynamic language I have used, including python, ruby, javascript(v8), and lua(jit).
  - graue 13y ago
    Faster than LuaJIT? At what? Did you run benchmarks to back that up? That's a very strong claim, and I've never heard anyone make it before. LuaJIT is unbelievably fast. I'd be extremely curious to see the proof. (As a side note, on some level it's hard for me to accept that Clojure is fast because using it feels gratingly slow — since all the tools take several seconds to do anything thanks to the JVM's startup time. `lein repl`: 4 seconds wait. `luajit`, or `python` for that matter: utterly instant.)
    - saosebastiao 13y ago
      No benchmarks, just a few small algorithm implementations (kmeans, random forest, ff neural net). Clojure was faster, although the difference was pretty trivial. I have been frustrated with Clojure lately because of startup time (I do a lot of CLI tools), and would love to use Luajit, but my coworkers hate when I write in languages other than Ruby or Clojure. For my own pet projects it is great.
      - graue 13y ago
        Well that's pretty darn cool to hear that Clojure can achieve LuaJIT's level of speed. But I agree, I feel Clojure just isn't suited for CLI tools at all, unfortunately. I know there are solutions that keep a background JVM ready and reuse it but I've never managed to get that to work smoothly.
- Mikeb85 13y ago
  How does Java compare to C or Fortran? And how much does it matter? Ruby and Python are incredibly popular despite being incredibly slow. Clojure has decent enough performance, plus easy parallelism/concurrency...
jdmichal 13y ago
Performance and language prettiness are also two different things. Again, when we're talking about "Big Data", the implication is that there is a very large number of rows being processed. That's nice that "adding lanes" looks pretty in Clojure, but it's not like it's impossible to do in Java. And if I can double or quadruple my throughput by switching to uglier Java code? And on top of that I drastically widen up the pool of potential employees? Well, this is starting to look like a pretty shut case from a business perspective. And that's also why I asked about whether naive Clojure script is performant, or whether you have to take so many non-obvious routes to eek out the performance that it loses "conciseness" as a point in its favor. (Disclaimer: I don't have recent performance numbers on Java vs Clojure; that's why I was asking for them. The double/quadruple numbers above were pulled from thin air.)
- tensor 13y ago
  In my experience it's always possible to get java level performance out of clojure when you need it, even if that ends up meaning that you essentially write java with sexpressions and macros. However, even for "medium data", when I find clojure too slow I fall back to C/C++. I've never found myself thinking "maybe I should write this in java." Unfortunately, I can't find good examples of modern performant clojure with benchmarks at the moment. As far as I understand, the alioth benchmarks are still out of date.

optimiz3 13y ago

This doesn't answer the author's question. We know the difference between performance and scalability. How does it perform compared to Java?

saosebastiao 13y ago
It is slower than java. It can approach Java with type annotations which aren't that hard to do. It is faster than any other dynamic language I have used, including python, ruby, javascript(v8), and lua(jit).
- graue 13y ago
  Faster than LuaJIT? At what? Did you run benchmarks to back that up? That's a very strong claim, and I've never heard anyone make it before. LuaJIT is unbelievably fast. I'd be extremely curious to see the proof. (As a side note, on some level it's hard for me to accept that Clojure is fast because using it feels gratingly slow — since all the tools take several seconds to do anything thanks to the JVM's startup time. `lein repl`: 4 seconds wait. `luajit`, or `python` for that matter: utterly instant.)
  - saosebastiao 13y ago
    No benchmarks, just a few small algorithm implementations (kmeans, random forest, ff neural net). Clojure was faster, although the difference was pretty trivial. I have been frustrated with Clojure lately because of startup time (I do a lot of CLI tools), and would love to use Luajit, but my coworkers hate when I write in languages other than Ruby or Clojure. For my own pet projects it is great.
    - graue 13y ago
      Well that's pretty darn cool to hear that Clojure can achieve LuaJIT's level of speed. But I agree, I feel Clojure just isn't suited for CLI tools at all, unfortunately. I know there are solutions that keep a background JVM ready and reuse it but I've never managed to get that to work smoothly.
Mikeb85 13y ago
How does Java compare to C or Fortran? And how much does it matter? Ruby and Python are incredibly popular despite being incredibly slow. Clojure has decent enough performance, plus easy parallelism/concurrency...

jdmichal 13y ago

Performance and language prettiness are also two different things. Again, when we're talking about "Big Data", the implication is that there is a very large number of rows being processed. That's nice that "adding lanes" looks pretty in Clojure, but it's not like it's impossible to do in Java. And if I can double or quadruple my throughput by switching to uglier Java code? And on top of that I drastically widen up the pool of potential employees? Well, this is starting to look like a pretty shut case from a business perspective. And that's also why I asked about whether naive Clojure script is performant, or whether you have to take so many non-obvious routes to eek out the performance that it loses "conciseness" as a point in its favor. (Disclaimer: I don't have recent performance numbers on Java vs Clojure; that's why I was asking for them. The double/quadruple numbers above were pulled from thin air.)

tensor 13y ago
In my experience it's always possible to get java level performance out of clojure when you need it, even if that ends up meaning that you essentially write java with sexpressions and macros. However, even for "medium data", when I find clojure too slow I fall back to C/C++. I've never found myself thinking "maybe I should write this in java." Unfortunately, I can't find good examples of modern performant clojure with benchmarks at the moment. As far as I understand, the alioth benchmarks are still out of date.