You need the (System/exit 0) when using a higher optimization setting and this is explicitly mentioned in the Quick Start. This is an upstream bug in Closure Compiler. They create a thread to increase the stack size for Java 6, this is legitimately a bug though as Closure Compiler only supports Java 7.
David On Wed, Mar 18, 2015 at 12:48 PM, Caspar Hasenclever <[email protected]> wrote: > Following the current Quick Start document at > https://github.com/clojure/clojurescript/wiki/Quick-Start, I found that > there is a roughly one minute long extra wait after closure optimizations > have been applied before the JVM exits. > > My setup: hello word example as on the Quick Start guide, build.clj is: > > (require 'cljs.closure) > > (cljs.closure/build "src" > {:output-to "out/main.js" > :verbose true}) > > With this build call (no optimizations), compile from cold is under 3s. > Adding simple optimizations to the above call: > > (cljs.closure/build "src" > {:output-to "out/main.js" > :optimizations :simple > :verbose true}) > > makes the process take over a minute. The CPU is only active for a few > seconds at the beginning, for the remainder of the time nothing appears > to be happening (the output file is done and remains unchanged after the > first few seconds). Looking at the process in jvisualvm shows threads > called jscompiler that are also idle after a bit of activity at the > beginning. My suspicion is that there is a timeout somewhere but I have > not found exactly where. It looks as if it is in Google Closure as I can't > find > any reference to threads called jscompiler in the ClojureScript sources. > > A Thread dump during the wait time shows a jscompiler thread to be waiting: > > "jscompiler" #16 prio=5 os_prio=0 tid=0x00007f2304efb800 nid=0x5032 > waiting on condition [0x00007f22e4713000] > java.lang.Thread.State: TIMED_WAITING (parking) > at sun.misc.Unsafe.park(Native Method) > - parking to wait for <0x000000008725e6f8> (a > java.util.concurrent.SynchronousQueue$TransferStack) > at > java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215) > at > java.util.concurrent.SynchronousQueue$TransferStack.awaitFulfill(SynchronousQueue.java:460) > at > java.util.concurrent.SynchronousQueue$TransferStack.transfer(SynchronousQueue.java:362) > at > java.util.concurrent.SynchronousQueue.poll(SynchronousQueue.java:941) > at > java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1066) > at > java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127) > at > java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) > at java.lang.Thread.run(Thread.java:745) > > Locked ownable synchronizers: > - None > > Adding a simple: > > (System/exit 0) > > after the cljs.closure/build call reduces compilation by almost exactly > a minute back down to 8 seconds with {:optimizations :simple}. > > System is Debian Linux (testing), Oracle JDK 8, java -version: > > java version "1.8.0_40" > Java(TM) SE Runtime Environment (build 1.8.0_40-b26) > Java HotSpot(TM) 64-Bit Server VM (build 25.40-b25, mixed mode) > > Compilation command line is: > > java -cp cljs.jar:src clojure.main build.clj > > Has anybody else experienced this? Is there a way to reduce the wait? > > Regards, > > Caspar > > -- > Note that posts from new members are moderated - please be patient with > your first post. > --- > You received this message because you are subscribed to the Google Groups > "ClojureScript" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/clojurescript. > -- Note that posts from new members are moderated - please be patient with your first post. --- You received this message because you are subscribed to the Google Groups "ClojureScript" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/clojurescript.
