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Comment by georgewsinger | Hacker News Reader

One of the weaknesses of Clojure on the JVM is its ridiculously long startup time. How fast does Frege start up on the JVM?

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It's okay, at least when you have SSD or at least decent RAM.

Here is an example:

    ingo@freguntu:~/Frege/frege$ time java -jar fregec.jar -version
    3.23.900
    0:00.22 62016k
    ingo@freguntu:~/Frege/frege$ ls -l fregec.jar -rw------- 1 ingo ingo 33426802 Mär  6 12:32 fregec.jar

Aren't you checking the Frege compiler, there?

The complaint about Clojure is that Clojure apps start slow. Frege compiles to Java and from there to bytecode, so you'd need to compare a hello world in both languages to answer the original question, I think.

The compiler is a Frege app.

22 milliseconds? Unless I'm mistaken that's blazing fast?

I believe that's 220ms. Which isn't too bad. But Clojure can usually match that if you AOT everything.

It's still too slow for serious command-line utils, though, so you're back to Haskell.

Or using a long-running system daemon to host the VM

On a server, it's a non-issue. On desktop, likely, too. Modern Android does AOT compilation. Hopefully by the time Frege is ready for Android this will not be a problem anymore.

Clojure is slow at startup because of the long list of classes have to be loaded at init I think.

It's the core namespace that is huge. Also clojure embeds all metadata etc, taking more time than necessary for a script runtime. Clojure guys discussed having multiple builds, a lean runtime for fast boot, and more featured one for repl usage (even more documentation embedded etc)

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