ivor区的大小比值
PermSize= 16.0MB #对应jvm启动参数-XX:PermSize=<value>:设置JVM堆的‘永生代’的初始大小
MaxPermSize=64.0MB #对应jvm启动参数-XX:MaxPermSize=<value>:设置JVM堆的‘永生代’的最大大小
Heap Usage: #堆内存分步
PS Young Generation
Eden Space: #Eden区内存分布
capacity = 20381696 (19.4375MB) #Eden区总容量
used = 20370032 (19.426376342773438MB) #Eden区已使用
free = 11664 (0.0111236572265625MB) #Eden区剩余容量
99.94277218147106% used #Eden区使用比率
From Space: #其中一个Survivor区的内存分布
capacity = 8519680 (8.125MB)
used = 32768 (0.03125MB)
free = 8486912 (8.09375MB)
0.38461538461538464% used
To Space: #另一个Survivor区的内存分布
capacity = 9306112 (8.875MB)
used = 0 (0.0MB)
free = 9306112 (8.875MB)
0.0% used
PS Old Generation #当前的Old区内存分布
capacity = 366280704 (349.3125MB)
used = 322179848 (307.25464630126953MB)
free = 44100856 (42.05785369873047MB)
87.95982001825573% used
PS Perm Generation #当前的 “永生代” 内存分布
capacity = 32243712 (30.75MB)
used = 28918584 (27.57891082763672MB)
free = 3325128 (3.1710891723632812MB)
89.68751488662348% used
<%@ page import="java.lang.management.*" %>
<%@ page import="java.util.*" %>
<html>
<head>
<title>JVM Memory Monitor</title>
</head>
<body>
<table border="0" width="100%">
<tr><td colspan="2" align="center"><h3>Memory MXBean</h3></td></tr>
<tr><td width="200">Heap Memory Usage</td><td><%=ManagementFactory.getMemoryMXBean().getHeapMemoryUsage()%></td></tr>
<tr><td>Non-Heap Memory Usage</td><td><%=ManagementFactory.getMemoryMXBean().getNonHeapMemoryUsage()%></td></tr>
<tr><td colspan="2"> </td></tr>
<tr><td colspan="2" align="center"><h3>Memory Pool MXBeans</h3></td></tr>
<%
Iterator iter = ManagementFactory.getMemoryPoolMXBeans().iterator();
while (iter.hasNext()) {
MemoryPoolMXBean item = (MemoryPoolMXBean) iter.next();
%>
<tr><td colspan="2">
<table border="0" width="100%" style="border: 1px #98AAB1 solid;">
<tr><td colspan="2" align="center"><b><%= item.getName() %></b></td></tr>
<tr><td width="200">Type</td><td><%= item.getType() %></td></tr>
<tr><td>Usage</td><td><%= item.getUsage() %></td></tr>
<tr><td>Peak Usage</td><td><%= item.getPeakUsage() %></td></tr>
<tr><td>Collection Usage</td><td><%= item.getCollectionUsage() %></td></tr>
</table>
</td></tr>
<tr><td colspan="2"> </td></tr>
<%} %>
</table>
</body>
</html>