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我在Ubuntu 11.04上使用Scala 2.9.0.final。在出現提示之前，從命令行啓動scala大約需要20秒。Scala REPL〜20secs啓動 - 這是正常的嗎？
我意識到我應該期待一些延遲，因爲它必須導致編譯器JAR文件，但我很難相信它應該是20秒 - 我擔心我可能有配置錯誤的東西。
編輯
所以，我想jstack，它給出了一個長時間的輸出就是上面我的頭。我看到一個線程在等待一個互斥鎖。但看輸出time：
21.96s user 0.66s system 135% cpu 16.711 total
這似乎是它花的週期體面的數額兩個內核上...所以也許它不只是阻止對當時互斥？
2011-07-28 11:45:02
Full thread dump OpenJDK 64-Bit Server VM (20.0-b11 mixed mode):
"Attach Listener" daemon prio=10 tid=0x00000000023ea000 nid=0x19a9 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"Thread-0" prio=10 tid=0x00007f7768304800 nid=0x19a8 runnable [0x00007f776cd92000]
java.lang.Thread.State: RUNNABLE
at scala.collection.generic.Growable$$anonfun$$plus$plus$eq$1.<init>(Growable.scala:48)
at scala.collection.generic.Growable$class.$plus$plus$eq(Growable.scala:48)
at scala.collection.mutable.ListBuffer.$plus$plus$eq(ListBuffer.scala:128)
at scala.collection.TraversableOnce$class.toList(TraversableOnce.scala:242)
at scala.collection.mutable.WrappedArray.toList(WrappedArray.scala:33)
at scala.collection.immutable.List$.apply(List.scala:434)
at scala.Option.toList(Option.scala:231)
at scala.tools.nsc.util.DirectoryClassPath.asURLs(ClassPath.scala:321)
at scala.tools.nsc.util.ClassPath.sortString(ClassPath.scala:284)
at scala.tools.nsc.util.ClassPath.hashCode(ClassPath.scala:289)
at scala.collection.mutable.FlatHashTable$HashUtils$class.elemHashCode(FlatHashTable.scala:349)
at scala.collection.mutable.HashSet.elemHashCode(HashSet.scala:39)
at scala.collection.mutable.FlatHashTable$class.containsEntry(FlatHashTable.scala:109)
at scala.collection.mutable.HashSet.containsEntry(HashSet.scala:39)
at scala.collection.mutable.HashSet.contains(HashSet.scala:55)
at scala.collection.GenSetLike$class.apply(GenSetLike.scala:44)
at scala.collection.mutable.HashSet.apply(HashSet.scala:39)
at scala.collection.SeqLike$$anonfun$distinct$1.apply(SeqLike.scala:505)
at scala.collection.LinearSeqOptimized$class.foreach(LinearSeqOptimized.scala:59)
at scala.collection.immutable.List.foreach(List.scala:45)
at scala.collection.SeqLike$class.distinct(SeqLike.scala:504)
at scala.collection.immutable.List.distinct(List.scala:45)
at scala.tools.util.PathResolver$Calculated$.containers(PathResolver.scala:206)
- locked <0x00000000faba8098> (a scala.tools.util.PathResolver$Calculated$)
at scala.tools.util.PathResolver.containers(PathResolver.scala:228)
at scala.tools.util.PathResolver.result(PathResolver.scala:231)
- locked <0x00000000faba8050> (a scala.tools.util.PathResolver)
at scala.tools.nsc.backend.JavaPlatform$class.classPath(JavaPlatform.scala:18)
at scala.tools.nsc.Global$$anon$2.classPath(Global.scala:54)
- locked <0x00000000faba7ff0> (a scala.tools.nsc.Global$$anon$2)
at scala.tools.nsc.backend.JavaPlatform$class.rootLoader(JavaPlatform.scala:19)
at scala.tools.nsc.Global$$anon$2.rootLoader(Global.scala:54)
at scala.tools.nsc.Global$$anon$2.rootLoader(Global.scala:54)
at scala.tools.nsc.Global.rootLoader(Global.scala:57)
at scala.tools.nsc.symtab.Definitions$definitions$.RootClass(Definitions.scala:138)
- locked <0x00000000faba5620> (a scala.tools.nsc.symtab.Definitions$definitions$)
at scala.tools.nsc.symtab.Definitions$definitions$.EmptyPackage(Definitions.scala:141)
- locked <0x00000000faba5620> (a scala.tools.nsc.symtab.Definitions$definitions$)
at scala.tools.nsc.symtab.Definitions$definitions$.EmptyPackageClass(Definitions.scala:142)
- locked <0x00000000faba5620> (a scala.tools.nsc.symtab.Definitions$definitions$)
at scala.tools.nsc.symtab.Definitions$definitions$.init(Definitions.scala:804)
at scala.tools.nsc.Global$Run.<init>(Global.scala:693)
at scala.tools.nsc.interpreter.IMain.scala$tools$nsc$interpreter$IMain$$_initialize(IMain.scala:120)
at scala.tools.nsc.interpreter.IMain$$anonfun$initialize$1.apply$mcZ$sp(IMain.scala:154)
at scala.tools.nsc.interpreter.IMain$$anonfun$initialize$2.apply(IMain.scala:154)
at scala.tools.nsc.interpreter.IMain$$anonfun$initialize$2.apply(IMain.scala:154)
at scala.concurrent.ThreadRunner$$anon$2$$anonfun$run$2.apply(ThreadRunner.scala:45)
at scala.concurrent.ThreadRunner.scala$concurrent$ThreadRunner$$tryCatch(ThreadRunner.scala:31)
at scala.concurrent.ThreadRunner$$anon$2.run(ThreadRunner.scala:45)
at java.lang.Thread.run(Thread.java:679)
"Low Memory Detector" daemon prio=10 tid=0x00007f77680b9000 nid=0x1996 runnable [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"C2 CompilerThread1" daemon prio=10 tid=0x00007f77680b6800 nid=0x1995 runnable [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"C2 CompilerThread0" daemon prio=10 tid=0x00007f77680b3800 nid=0x1994 runnable [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"Signal Dispatcher" daemon prio=10 tid=0x00007f77680b2000 nid=0x1993 runnable [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"Finalizer" daemon prio=10 tid=0x00007f7768092800 nid=0x1992 in Object.wait() [0x00007f776e27c000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x00000000fb2d82d0> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:133)
- locked <0x00000000fb2d82d0> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:149)
at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:177)
"Reference Handler" daemon prio=10 tid=0x00007f7768091000 nid=0x1991 in Object.wait() [0x00007f776e37d000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x00000000fb2d8370> (a java.lang.ref.Reference$Lock)
at java.lang.Object.wait(Object.java:502)
at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:133)
- locked <0x00000000fb2d8370> (a java.lang.ref.Reference$Lock)
"main" prio=10 tid=0x0000000001db4800 nid=0x198d in Object.wait() [0x00007f7775067000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x00000000fab8d110> (a scala.concurrent.SyncVar)
at java.lang.Object.wait(Object.java:502)
at scala.concurrent.SyncVar.get(SyncVar.scala:22)
- locked <0x00000000fab8d110> (a scala.concurrent.SyncVar)
at scala.concurrent.ThreadRunner$$anonfun$submit$1.apply(ThreadRunner.scala:48)
at scala.Function0$class.apply$mcZ$sp(Function0.scala:34)
at scala.runtime.AbstractFunction0.apply$mcZ$sp(AbstractFunction0.scala:12)
at scala.tools.nsc.interpreter.IMain.global(IMain.scala:162)
- locked <0x00000000fb2d8580> (a scala.tools.nsc.interpreter.ILoop$ILoopInterpreter)
at scala.tools.nsc.interpreter.JLineCompletion.<init>(JLineCompletion.scala:17)
at scala.tools.nsc.interpreter.ILoop.chooseReader(ILoop.scala:791)
at scala.tools.nsc.interpreter.ILoop.process(ILoop.scala:807)
at scala.tools.nsc.MainGenericRunner.runTarget$1(MainGenericRunner.scala:67)
at scala.tools.nsc.MainGenericRunner.process(MainGenericRunner.scala:80)
at scala.tools.nsc.MainGenericRunner$.main(MainGenericRunner.scala:89)
at scala.tools.nsc.MainGenericRunner.main(MainGenericRunner.scala)
"VM Thread" prio=10 tid=0x00007f776808a000 nid=0x1990 runnable
"GC task thread#0 (ParallelGC)" prio=10 tid=0x0000000001dc0000 nid=0x198e runnable
"GC task thread#1 (ParallelGC)" prio=10 tid=0x0000000001dc1800 nid=0x198f runnable
"VM Periodic Task Thread" prio=10 tid=0x00007f77680bb800 nid=0x1997 waiting on condition
JNI global references: 1010
它在我的電腦（Scala 2.7.7final，Ubuntu 11.04）中眨眼之間即可打開。你能否嘗試捕獲初始化解釋器的堆棧轉儲？使用'jps'和'jstack'。 –
這聽起來很正常。假設你的硬件沒有損壞，並且你沒有運行Intel 80386，啓動速度應該非常快。你可以試試2.9.1的最新RC，並檢查它是否更好。 – soc
Scala 2.9.0的啓動速度比2.8.1慢得多。這將在Scala 2.9.1 AFAIK中解決。在我的2.66 GHz OS X機器上，需要6秒鐘，這已經非常慢了。 2.8.1比較需要2秒！但20秒聽起來像你有一個嚴重的問題 –