This is something I've thought/talked about for some time now. In reality this is one of the reasons I started Mjolnir. I would like to see an implementation of Clojure on LLVM. Mjolnir is several months away from being able to handle a project like this, but I took the time tonight to type up my thoughts on the topic.
https://github.com/halgari/clojure-metal/blob/master/README.md I'd love to hear anyone's input on this doc. I just typed this up, so it's a bit rough, but it should communicate some of the ideas I have. Timothy Baldridge On Thu, Mar 28, 2013 at 7:26 PM, Mikera <mike.r.anderson...@gmail.com>wrote: > On Friday, 29 March 2013 05:45:53 UTC+8, Laurent PETIT wrote: > >> 2013/3/28 Marko Topolnik <marko.t...@gmail.com>: >> > Or you may have just a trivial requirement for a program that both >> starts >> > and executes quickly. >> >> To what extent would an LLVM / C version of a Clojure program not >> incur startup penalty as the JVM does. >> >> As far as I understand it, the startup cost is manyfold: >> 1/ JVM startup >> 2/ loading of Clojure Core >> 3/ loading of non-lazy parts of your application (generally from >> loading a global namespace to invoke its -main function) >> > > In my experience 1) is a small fraction of the total. A trivial "hello > world" Java program runs in less than 0.1sec on my machine, which proves > that JVM startup isn't really important. Or at least, far less important > than most people think. > > >> >> I know AOT compilation can somehow reduce load-time of 2/ and 3/, but >> not bring them to zero. As far as I understand it, all the namespaces >> involved in your application will still have to be linearly executed, >> in a depth-first manner following the graph of namespace dependencies >> + loaded configuration files etc. Only the compilations of functions >> will be optimized into loading of their corresponding classes. >> >> So, short of having a "image-like" environment, I wonder what the time >> taken to do 2/ + 3/ would be in LLVM / C versions of Clojure. >> > > It might even be slower in LLVM / C, unless you can at least match the JVM > in terms of JIT optimisation and garbage collector efficiency, which in > turn affects the runtime for 2+3 (I believe a garbage collector is a > requirement to execute Clojure?). Beating the JVM isn't an easy feat. > > Something I would be very interested in would be enhancements to Clojure > that allow for lazy compilation, i.e. deferring compilation of parts of > your application or Clojure Core until they are directly invoked for the > first time. This is probably going to be the most promising approach for > reducing Clojure startup time, although I expect it would require some > breaking changes. > > -- > -- > You received this message because you are subscribed to the Google > Groups "Clojure" group. > To post to this group, send email to clojure@googlegroups.com > Note that posts from new members are moderated - please be patient with > your first post. > To unsubscribe from this group, send email to > clojure+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/clojure?hl=en > --- > You received this message because you are subscribed to the Google Groups > "Clojure" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to clojure+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- “One of the main causes of the fall of the Roman Empire was that–lacking zero–they had no way to indicate successful termination of their C programs.” (Robert Firth) -- -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
