记录器在 logger.info 期间冻结

Question

当使用 Logback 调用 log.info(...) 时，我的后台工作（经常）卡住了：

"pool-5-thread-1" #30 prio=5 os_prio=0 tid=0x00007f11c4ff2000 nid=0x100 waiting on condition [0x00007f11bd21a000]
   java.lang.Thread.State: WAITING (parking)
    at sun.misc.Unsafe.park(Native Method)
    - parking to wait for  <0x00000000db93e3a8> (a java.util.concurrent.locks.ReentrantLock$FairSync)
    at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(AbstractQueuedSynchronizer.java:870)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(AbstractQueuedSynchronizer.java:1199)
    at java.util.concurrent.locks.ReentrantLock$FairSync.lock(ReentrantLock.java:224)
    at java.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:285)
    at ch.qos.logback.core.OutputStreamAppender.subAppend(OutputStreamAppender.java:217)
    at ch.qos.logback.core.OutputStreamAppender.append(OutputStreamAppender.java:103)
    at ch.qos.logback.core.UnsynchronizedAppenderBase.doAppend(UnsynchronizedAppenderBase.java:88)
    at ch.qos.logback.core.spi.AppenderAttachableImpl.appendLoopOnAppenders(AppenderAttachableImpl.java:48)
    at ch.qos.logback.classic.Logger.appendLoopOnAppenders(Logger.java:273)
    at ch.qos.logback.classic.Logger.callAppenders(Logger.java:260)
    at ch.qos.logback.classic.Logger.buildLoggingEventAndAppend(Logger.java:442)
    at ch.qos.logback.classic.Logger.filterAndLog_0_Or3Plus(Logger.java:396)
    at ch.qos.logback.classic.Logger.info(Logger.java:600)
    at com.website.configuration.BackgroundJobs.lambda$run$2(BackgroundJobs.java:410)
    at com.website.configuration.BackgroundJobs$$Lambda$85/1402118067.accept(Unknown Source)
    at java.util.Spliterators$ArraySpliterator.forEachRemaining(Spliterators.java:948)
    at java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:647)
    at com.website.configuration.BackgroundJobs.run(BackgroundJobs.java:396)
    at sun.reflect.GeneratedMethodAccessor59.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.springframework.scheduling.support.ScheduledMethodRunnable.run(ScheduledMethodRunnable.java:65)
    at org.springframework.scheduling.support.DelegatingErrorHandlingRunnable.run(DelegatingErrorHandlingRunnable.java:54)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)

它位于此 state 中，直到我重新启动服务器才进展。

任何想法为什么会发生这种情况？

我正在使用 spring boot 1.3.1.RELEASE 和 org.springframework.boot:spring-boot-starter-web:1.3.1.RELEASE，它使用 logback-classic-1.1.3。

我在 @Controllers 和 @Configuration 类中定义我的记录器，如下所示：

final Logger log = LoggerFactory.getLogger(getClass().getName());

这是另一个显示相同问题的线程转储，但这次 log.info 是从不同的 class 调用的：

"pool-5-thread-1" #30 prio=5 os_prio=0 tid=0x00007f96f5cdc800 nid=0x100 waiting on condition [0x00007f9737d66000]
   java.lang.Thread.State: WAITING (parking)
    at sun.misc.Unsafe.park(Native Method)
    - parking to wait for  <0x00000000db6501f0> (a java.util.concurrent.locks.ReentrantLock$FairSync)
    at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(AbstractQueuedSynchronizer.java:870)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(AbstractQueuedSynchronizer.java:1199)
    at java.util.concurrent.locks.ReentrantLock$FairSync.lock(ReentrantLock.java:224)
    at java.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:285)
    at ch.qos.logback.core.OutputStreamAppender.subAppend(OutputStreamAppender.java:217)
    at ch.qos.logback.core.OutputStreamAppender.append(OutputStreamAppender.java:103)
    at ch.qos.logback.core.UnsynchronizedAppenderBase.doAppend(UnsynchronizedAppenderBase.java:88)
    at ch.qos.logback.core.spi.AppenderAttachableImpl.appendLoopOnAppenders(AppenderAttachableImpl.java:48)
    at ch.qos.logback.classic.Logger.appendLoopOnAppenders(Logger.java:273)
    at ch.qos.logback.classic.Logger.callAppenders(Logger.java:260)
    at ch.qos.logback.classic.Logger.buildLoggingEventAndAppend(Logger.java:442)
    at ch.qos.logback.classic.Logger.filterAndLog_0_Or3Plus(Logger.java:396)
    at ch.qos.logback.classic.Logger.info(Logger.java:600)
    at com.website.service.JobScheduler.scheduleJob(JobScheduler.java:55)
    at com.website.configuration.BackgroundJobs.lambda$run$2(BackgroundJobs.java:411)
    at com.website.configuration.BackgroundJobs$$Lambda$85/1061458720.accept(Unknown Source)
    at java.util.Spliterators$ArraySpliterator.forEachRemaining(Spliterators.java:948)
    at java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:647)
    at com.website.configuration.BackgroundJobs.run(BackgroundJobs.java:396)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.springframework.scheduling.support.ScheduledMethodRunnable.run(ScheduledMethodRunnable.java:65)
    at org.springframework.scheduling.support.DelegatingErrorHandlingRunnable.run(DelegatingErrorHandlingRunnable.java:54)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at java.lang.Thread.run(Thread.java:748)

Answer 1

看起来实际的问题是我并行记录了太多，以至于记录器正在等待所有其他日志成为 output 以便它可以继续。

通过减少我正在做的日志记录量来改善这种情况。

稍后将研究异步日志库（即不阻塞的记录器）。