为什么broker使用了太多内存？

JVM Parameters :

-Xms1g -Xmx1g -Xmn512m -XX:MaxDirectMemorySize=6g -Dio.netty.maxDirectMemory=1g

broker.properties :

transientStorePoolEnable=true transientStorePoolSize=5

当borker正在运行时，内存使用率为：

[top] :

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND xxx xxx 20 0 66.5g 9.6g 3.3g S 6.7 15.4 15:31.46 java

[Native Memory Tracking] :

Total: reserved=8703173KB, committed=7428985KB - Java Heap (reserved=1048576KB, committed=1048576KB) (mmap: reserved=1048576KB, committed=1048576KB)

• Class (reserved=1076036KB, committed=30224KB) (classes #4402) (malloc=836KB #10413) (mmap: reserved=1075200KB, committed=29388KB)

• Thread (reserved=544671KB, committed=544671KB) (thread #530) (stack: reserved=543388KB, committed=543388KB) (malloc=663KB #2695) (arena=620KB #1043)

• Code (reserved=253682KB, committed=27354KB) (malloc=4082KB #6258) (mmap: reserved=249600KB, committed=23272KB)

• GC (reserved=151361KB, committed=151361KB) (malloc=79681KB #5496) (mmap: reserved=71680KB, committed=71680KB)

• Compiler (reserved=751KB, committed=751KB) (malloc=620KB #907) (arena=131KB #18)

• Internal (reserved=5618182KB, committed=5618182KB) (malloc=5618150KB #12872) (mmap: reserved=32KB, committed=32KB)

• Symbol (reserved=5938KB, committed=5938KB) (malloc=4012KB #30016) (arena=1926KB #1)

• Native Memory Tracking (reserved=1153KB, committed=1153KB) (malloc=53KB #572) (tracking overhead=1100KB)

• Arena Chunk (reserved=777KB, committed=777KB) (malloc=777KB)

• Unknown (reserved=2048KB, committed=0KB) (mmap: reserved=2048KB, committed=0KB)

为什么broker 用 'RES' 9.6G？

原提问者GitHub用户ozw999