问题描述：
某一个系统生产环境java进程占用2.3GB内存，但是堆的最大内存1.5GB，等超过容器内存2.5之后导致容器会重启,启动参数为：-Xms1536M -Xmx1536M --XX:NativeMemoryTracking=detail -Xss256k -XX:MaxDirectMemorySize=1024m -XX:MetaspaceSize=128m -XX:MaxMetaspaceSize=512m -XX:CompressedClassSpaceSize=256m -XX:ReservedCodeCacheSize=256m -XX:MaxRAMPercentage=45 -XX:InitialRAMPercentage=45 -javaagent:xxx

启动后1.5G到2.3G对比：

Native Memory Tracking:

(Omitting categories weighting less than 1MB)

Total: reserved=2479MB +11MB, committed=2009MB +28MB

-                 Java Heap (reserved=1536MB, committed=1536MB)
                            (mmap: reserved=1536MB, committed=1536MB)

-                     Class (reserved=259MB, committed=25MB +1MB)
                            (classes #34740 +1111)
                            (  instance classes #32624 +1069, array classes #2116 +42)
                            (malloc=3MB #81814 +7837)
                            (mmap: reserved=256MB, committed=22MB +1MB)
                           : (  Metadata)
                            (    reserved=152MB +8MB, committed=146MB +7MB)
                            (    used=146MB +7MB)
                            (    waste=1MB =0.42%)
                           : (  Class space)
                            (    reserved=256MB, committed=22MB +1MB)
                            (    used=21MB +1MB)
                            (    waste=1MB =2.84%)

-                    Thread (reserved=55MB, committed=19MB)
                            (thread #0)
                            (stack: reserved=55MB, committed=18MB)

-                      Code (reserved=263MB +2MB, committed=70MB +19MB)
                            (malloc=5MB +2MB #23580 +3551)
                            (mmap: reserved=258MB, committed=65MB +18MB)

-                        GC (reserved=101MB, committed=101MB)
                            (malloc=12MB #37365 +7177)
                            (mmap: reserved=89MB, committed=89MB)

-                  Compiler (reserved=1MB, committed=1MB)
                            (malloc=1MB #2339 +127)

-                  Internal (reserved=4MB +1MB, committed=4MB +1MB)
                            (malloc=4MB +1MB #41556 +11725)

-                     Other (reserved=37MB, committed=37MB)
                            (malloc=37MB #182 +15)

-                    Symbol (reserved=37MB +1MB, committed=37MB +1MB)
                            (malloc=35MB +1MB #887891 +22181)
                            (arena=2MB #1)

-    Native Memory Tracking (reserved=17MB +1MB, committed=17MB +1MB)
                            (malloc=1MB #10625 +4822)
                            (tracking overhead=17MB +1MB)

-        Shared class space (reserved=12MB, committed=12MB)
                            (mmap: reserved=12MB, committed=12MB)

-               Arena Chunk (reserved=1MB -3MB, committed=1MB -3MB)
                            (malloc=1MB -3MB)

-                    Module (reserved=1MB, committed=1MB)
                            (malloc=1MB #4798 +80)

-                 Metaspace (reserved=153MB +8MB, committed=147MB +7MB)
                            (malloc=1MB #666 +33)
                            (mmap: reserved=152MB +8MB, committed=146MB +7MB)



复制