Linux tomcat9 java.lang.OutOfMemoryError: Java heap space 解决方法

错误

tomcat9 出现这样的错误日志，可能会造成tomcat挂掉，这是由于可使用内存不足造成的。

01-May-2020 12:31:09.411 SEVERE [https-jsse-nio-443-exec-21] org.apache.coyote.AbstractProtocol$ConnectionHandler.process Failed to complete processing of a request
java.lang.OutOfMemoryError: Java heap space
01-May-2020 12:31:43.250 SEVERE [Catalina-utility-1] org.apache.catalina.core.ContainerBase.threadStart Exception processing background thread
java.util.concurrent.ExecutionException: java.lang.OutOfMemoryError: Java heap space
at java.util.concurrent.FutureTask.report(FutureTask.java:122)
at java.util.concurrent.FutureTask.get(FutureTask.java:192)
at org.apache.catalina.core.ContainerBase.threadStart(ContainerBase.java:1276)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessorMonitor.run(ContainerBase.java:1322)
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$Worker.run(ThreadPoolExecutor.java:624)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.OutOfMemoryError: Java heap space

解决方法

解决方法也很简单：在找到tomcat安装目录的里bin子目录中的 catalina.sh，
在文件开头加入下面语句，定义tomcat可使用内存，这里设置了最小4096m（4G），最大8192m（8G），可以根据需要自行调整。

JAVA_OPTS=”$JAVA_OPTS -Xms4096m -Xmx8192m”

文件内容如下：

#   LOGGING_MANAGER (Optional) Override Tomcat's logging manager
#                   Example (all one line)
#                   LOGGING_MANAGER="-Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager"
#
#   UMASK           (Optional) Override Tomcat's default UMASK of 0027
#
#   USE_NOHUP       (Optional) If set to the string true the start command will
#                   use nohup so that the Tomcat process will ignore any hangup
#                   signals. Default is "false" unless running on HP-UX in which
#                   case the default is "true"
# -----------------------------------------------------------------------------

#My config
JAVA_OPTS="$JAVA_OPTS -Xms4096m -Xmx8192m"

# OS specific support.  $var _must_ be set to either true or false.

然后重启tomcat，如果启动信息有设置的信息，表示设置成功了：