大并发下关闭Tomcat之后日志报错?报错

使用Jemeter做压测启动500个线程 执行10分钟之后然后停掉Jemeter 我在把Tomcat停掉就会报

信息: Illegal access: this web application instance has been stopped already.  Could not load ch.qos.logback.core.status.WarnStatus.  The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact.
java.lang.IllegalStateException
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1777)
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1735)
    at ch.qos.logback.classic.LoggerContext.noAppenderDefinedWarning(LoggerContext.java:175)
    at ch.qos.logback.classic.Logger.callAppenders(Logger.java:267)
    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.debug(Logger.java:503)
    at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:612)

Exception in thread "org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-8" java.lang.NoClassDefFoundError: ch/qos/logback/core/status/WarnStatus
    at ch.qos.logback.classic.LoggerContext.noAppenderDefinedWarning(LoggerContext.java:175)
    at ch.qos.logback.classic.Logger.callAppenders(Logger.java:267)
    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.debug(Logger.java:503)
    at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:612)
Caused by: java.lang.ClassNotFoundException: ch.qos.logback.core.status.WarnStatus
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1892)
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1735)
    ... 6 more
ERROR: JDWP Unable to get JNI 1.2 environment, jvm->GetEnv() return code = -2
JDWP exit error AGENT_ERROR_NO_JNI_ENV(183):  [util.c:838]
开始我以为Caused by: java.lang.ClassNotFoundException: ch.qos.logback.core.status.WarnStatus不存在但是这个类其实是存在的  我要是启动tomcat 不做压测正常关闭就没问题，请问这是什么问题