jmap -heap 8179
时间: 2024-06-17 07:07:11 浏览: 144
`jmap`是JDK自带的一款内存分析工具,可以用来生成堆转储快照。`jmap`命令提供了多种选项和参数,其中`-heap`选项可以用于打印Java进程堆的详细信息,包括堆的配置、使用情况等。
假设`8179`是Java进程的进程ID,那么执行如下命令可以打印出该Java进程的堆信息:
```shell
jmap -heap 8179
```
输出结果类似于:
```
Attaching to process ID 8179, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 25.152-b16
using thread-local object allocation.
Parallel GC with 4 thread(s)
Heap Configuration:
MinHeapFreeRatio = 0
MaxHeapFreeRatio = 100
MaxHeapSize = 2147483648 (2048.0MB)
NewSize = 44564480 (42.5MB)
MaxNewSize = 715849728 (682.5MB)
OldSize = 89653248 (85.5MB)
NewRatio = 2
SurvivorRatio = 8
MetaspaceSize = 268435456 (256.0MB)
CompressedClassSpaceSize = 1073741824 (1024.0MB)
MaxMetaspaceSize = 17592186044415 MB
G1HeapRegionSize = 1048576 (1.0MB)
Heap Usage:
PS Young Generation
Eden Space:
capacity = 251658240 (240.0MB)
used = 64849168 (61.849082946777344MB)
free = 186809072 (178.15091705322266MB)
25.758784566015415% used
From Space:
capacity = 4194304 (4.0MB)
used = 4194304 (4.0MB)
free = 0 (0.0MB)
100.0% used
To Space:
capacity = 4194304 (4.0MB)
used = 0 (0.0MB)
free = 4194304 (4.0MB)
0.0% used
PS Old Generation
capacity = 524288000 (500.0MB)
used = 0 (0.0MB)
free = 524288000 (500.0MB)
0.0% used
30863 interned Strings occupying 3338080 bytes.
```
输出结果包括了两部分信息,第一部分为堆的配置,包括了最小堆空闲比例、最大堆空闲比例、最大堆大小、新生代大小、新生代最大大小、老年代大小、新生代/老年代大小比例、幸存者区大小比例、元空间大小、压缩类空间大小和G1堆区域大小等。第二部分为堆的使用情况,包括了新生代和老年代的使用情况、堆空间使用率等。