JVM调优命令-jstat

痛定思痛。 2022-05-21 02:07 334阅读 0赞

JVM Statistics Monitoring Tool，是用于监视虚拟机运行时状态信息的命令，它可以显示出虚拟机进程中的类装载、内存、垃圾收集、JIT编译等运行数据。【性能分析】

命令格式

参数

\[options\] : 操作参数， 一般使用 -gcutil 查看gc情况  
VMID : 本地虚拟机进程ID， 即当前运行的java进程号  
\[interval\] : 连续输出的时间间隔，单位为秒或者毫秒  
\[count\] : 连续输出的次数，如果缺省打印无数次

**option 参数总览**

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 <thead> 
  <tr> 
   <th style="border-color:#C0C0C0;border-collapse:collapse;background:rgb(247,247,247);">Option</th> 
   <th style="border-color:#C0C0C0;border-collapse:collapse;background:rgb(247,247,247);">Displays</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">class</td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">类加载的行为统计。Statistics on the behavior of the class loader.</td> 
  </tr> 
  <tr style="background-color:rgb(248,248,248);"> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">compiler</td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">HotSpt JIT编译器行为统计。Statistics of the behavior of the HotSpot Just-in-Time compiler.</td> 
  </tr> 
  <tr> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">gc</td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">垃圾回收堆的行为统计。Statistics of the behavior of the garbage collected heap.</td> 
  </tr> 
  <tr style="background-color:rgb(248,248,248);"> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">gccapacity</td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">各个垃圾回收代容量(young,old,perm)和他们相应的空间统计。Statistics of the capacities of the generations and their corresponding spaces.</td> 
  </tr> 
  <tr> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">gcutil</td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">垃圾回收统计概述（百分比）。Summary of garbage collection statistics.</td> 
  </tr> 
  <tr style="background-color:rgb(248,248,248);"> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">gccause</td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">垃圾收集统计概述（同-gcutil），附加最近两次垃圾回收事件的原因。Summary of garbage collection statistics (same as -gcutil), with the cause of the last and</td> 
  </tr> 
  <tr> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">gcnew</td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">新生代行为统计。Statistics of the behavior of the new generation.</td> 
  </tr> 
  <tr style="background-color:rgb(248,248,248);"> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">gcnewcapacity</td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">新生代与其相应的内存空间的统计。Statistics of the sizes of the new generations and its corresponding spaces.</td> 
  </tr> 
  <tr> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">gcold</td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">年老代和永生代行为统计。Statistics of the behavior of the old and permanent generations.</td> 
  </tr> 
  <tr style="background-color:rgb(248,248,248);"> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">gcoldcapacity</td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">年老代行为统计。Statistics of the sizes of the old generation.</td> 
  </tr> 
  <tr> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">gcpermcapacity</td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">永生代行为统计。Statistics of the sizes of the permanent generation.</td> 
  </tr> 
  <tr style="background-color:rgb(248,248,248);"> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">printcompilation</td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;">HotSpot编译方法统计。HotSpot compilation method statistics.</td> 
  </tr> 
 </tbody> 
</table>

**option 参数详解**

**-class **（监视类装载、卸载数量、总空间以及耗费的时间）

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    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      1 
    </div> 
    <div style="background-image:none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      2 
    </div> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      3 
    </div> 
    <div style="background-image:none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      4 
    </div></td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
    <div style="background:none;border:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">[root@localhost bin]</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,130,0);"># jstat -class 4513</code> 
     </div> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">Loaded&nbsp; Bytes&nbsp; Unloaded&nbsp; Bytes&nbsp;&nbsp;&nbsp;&nbsp; Time &nbsp;</code> 
     </div> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">&nbsp;8455 17240.8&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0&nbsp;&nbsp;&nbsp;&nbsp; 0.0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 15.47</code> 
     </div> 
    </div></td> 
  </tr> 
 </tbody> 
</table>

Loaded : 加载class的数量  
Bytes : class字节大小  
Unloaded : 未加载class的数量  
Bytes : 未加载class的字节大小  
Time : 加载时间

**-compiler**（输出JIT编译过的方法数量耗时等）

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    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      1 
    </div> 
    <div style="background-image:none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      2 
    </div> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      3 
    </div></td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
    <div style="background:none;border:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">[root@localhost bin]</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,130,0);"># jstat -compiler 4513</code> 
     </div> 
     <div style="background-image:none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">Compiled Failed Invalid&nbsp;&nbsp; Time&nbsp;&nbsp; FailedType FailedMethod</code> 
     </div> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;&nbsp;&nbsp;&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">1255&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0&nbsp;&nbsp;&nbsp; 16.47&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0</code> 
      <span style="color:inherit;font-family:inherit;line-height:inherit;text-align:center;white-space:pre-wrap;background-color:transparent;"> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; </span> 
     </div> 
    </div></td> 
  </tr> 
 </tbody> 
</table>

Compiled : 编译数量  
Failed : 编译失败数量  
Invalid : 无效数量  
Time : 编译耗时  
FailedType : 失败类型  
FailedMethod : 失败方法的全限定名

**-gc**（垃圾回收堆的行为统计，常用命令）

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    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      1 
    </div> 
    <div style="background-image:none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      2 
    </div> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      3 
    </div></td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
    <div style="background:none;border:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">[root@localhost bin]</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,130,0);"># jstat -gc 4513</code> 
     </div> 
     <div style="background-image:none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">S0C&nbsp;&nbsp;&nbsp; S1C&nbsp;&nbsp;&nbsp; S0U&nbsp;&nbsp;&nbsp; S1U&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; EC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; EU&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; OC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; OU&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; PC&nbsp;&nbsp;&nbsp;&nbsp; PU&nbsp;&nbsp;&nbsp; YGC&nbsp;&nbsp;&nbsp;&nbsp; YGCT&nbsp;&nbsp;&nbsp; FGC&nbsp;&nbsp;&nbsp; FGCT&nbsp;&nbsp;&nbsp;&nbsp; GCT&nbsp;&nbsp; </code> 
     </div> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">52224.0 53248.0 19364.2&nbsp; 0.0&nbsp;&nbsp; 804864.0 74967.7&nbsp;&nbsp; 168448.0&nbsp;&nbsp; 80595.4&nbsp;&nbsp; 52736.0 52628.1&nbsp;&nbsp;&nbsp;&nbsp; 10&nbsp;&nbsp;&nbsp; 0.232&nbsp;&nbsp; 0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0.000&nbsp;&nbsp;&nbsp; 0.232</code> 
     </div> 
    </div></td> 
  </tr> 
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</table>

C即Capacity 总容量，U即Used 已使用的容量

S0C : survivor0区的总容量  
S1C : survivor1区的总容量  
S0U : survivor0区已使用的容量  
S1C : survivor1区已使用的容量  
EC : Eden区的总容量  
EU : Eden区已使用的容量  
OC : Old区的总容量  
OU : Old区已使用的容量  
PC  : 当前perm的容量 (KB)  
PU  : perm的使用 (KB)  
YGC : 新生代垃圾回收次数  
YGCT : 新生代垃圾回收时间  
FGC : 老年代垃圾回收次数  
FGCT : 老年代垃圾回收时间  
GCT : 垃圾回收总消耗时间

这个命令意思就是每隔2000ms输出4513的gc情况，一共输出2次

**-gccapacity**(同-gc，还会输出Java堆各区域使用到的最大、最小空间)

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      1 
    </div> 
    <div style="background-image:none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      2 
    </div> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      3 
    </div></td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
    <div style="background:none;border:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">[root@localhost bin]</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,130,0);"># jstat -gccapacity 4513 </code> 
     </div> 
     <div style="background-image:none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">NGCMN&nbsp;&nbsp;&nbsp; NGCMX&nbsp;&nbsp;&nbsp;&nbsp; NGC&nbsp;&nbsp;&nbsp;&nbsp; S0C&nbsp;&nbsp; S1C&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; EC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; OGCMN&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; OGCMX&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; OGC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; OC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; PGCMN&nbsp;&nbsp;&nbsp; PGCMX&nbsp;&nbsp;&nbsp;&nbsp; PGC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; PC&nbsp;&nbsp;&nbsp;&nbsp; YGC&nbsp;&nbsp;&nbsp; FGC </code> 
     </div> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">84480.0 1349632.0 913408.0 54272.0 51200.0 502784.0&nbsp;&nbsp; 168448.0&nbsp; 2699264.0&nbsp;&nbsp; 168448.0&nbsp;&nbsp; 168448.0&nbsp; 21504.0&nbsp; 83968.0&nbsp; 51712.0&nbsp; 51712.0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 9&nbsp;&nbsp;&nbsp;&nbsp; 0</code> 
     </div> 
    </div></td> 
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</table>

NGCMN : 新生代占用的最小空间  
NGCMX : 新生代占用的最大空间  
OGCMN : 老年代占用的最小空间  
OGCMX : 老年代占用的最大空间  
OGC：当前年老代的容量 (KB)  
OC：当前年老代的空间 (KB)  
PGCMN : perm占用的最小空间  
PGCMX : perm占用的最大空间

**-gcutil**（同-gc，输出的是已使用空间占总空间的百分比）

<table style="border:1px solid #C0C0C0;width:920px;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
 <tbody style="background:none;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
  <tr style="background:none;border-top:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;color:rgb(175,175,175);"> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      1 
    </div> 
    <div style="background-image:none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      2 
    </div> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      3 
    </div></td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
    <div style="background:none;border:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">[root@localhost bin]</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,130,0);"># jstat -gcutil 4513</code> 
     </div> 
     <div style="background-image:none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">S0&nbsp;&nbsp;&nbsp;&nbsp; S1&nbsp;&nbsp;&nbsp;&nbsp; E&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; O&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; P&nbsp;&nbsp;&nbsp;&nbsp; YGC&nbsp;&nbsp;&nbsp;&nbsp; YGCT&nbsp;&nbsp;&nbsp; FGC&nbsp;&nbsp;&nbsp; FGCT&nbsp;&nbsp;&nbsp;&nbsp; GCT&nbsp;&nbsp; </code> 
     </div> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">0.00&nbsp; 79.23&nbsp; 38.90&nbsp; 39.92&nbsp; 99.74&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 9&nbsp;&nbsp;&nbsp; 0.198&nbsp;&nbsp;&nbsp;&nbsp; 0&nbsp;&nbsp;&nbsp; 0.000&nbsp;&nbsp;&nbsp; 0.198</code> 
     </div> 
    </div></td> 
  </tr> 
 </tbody> 
</table>

**-gccause**（垃圾收集统计概述（同-gcutil），附加最近两次垃圾回收事件的原因）

<table style="border:1px solid #C0C0C0;width:920px;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
 <tbody style="background:none;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
  <tr style="background:none;border-top:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;color:rgb(175,175,175);"> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      1 
    </div> 
    <div style="background-image:none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      2 
    </div> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      3 
    </div></td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
    <div style="background:none;border:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">[root@localhost bin]</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,130,0);"># jstat -gccause 4513</code> 
     </div> 
     <div style="background-image:none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">S0&nbsp;&nbsp;&nbsp;&nbsp; S1&nbsp;&nbsp;&nbsp;&nbsp; E&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; O&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; P&nbsp;&nbsp;&nbsp;&nbsp; YGC&nbsp;&nbsp;&nbsp;&nbsp; YGCT&nbsp;&nbsp;&nbsp; FGC&nbsp;&nbsp;&nbsp; FGCT&nbsp;&nbsp;&nbsp;&nbsp; GCT&nbsp;&nbsp;&nbsp; LGCC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; GCC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </code> 
     </div> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">0.00&nbsp; 79.23&nbsp; 39.37&nbsp; 39.92&nbsp; 99.74&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 9&nbsp;&nbsp;&nbsp; 0.198&nbsp;&nbsp;&nbsp;&nbsp; 0&nbsp;&nbsp;&nbsp; 0.000&nbsp;&nbsp;&nbsp; 0.198 Allocation Failure&nbsp;&nbsp; No GC</code> 
     </div> 
    </div></td> 
  </tr> 
 </tbody> 
</table>

LGCC：最近垃圾回收的原因  
GCC：当前垃圾回收的原因

**-gcnew**（统计新生代行为）

<table style="border:1px solid #C0C0C0;width:920px;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
 <tbody style="background:none;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
  <tr style="background:none;border-top:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;color:rgb(175,175,175);"> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      1 
    </div> 
    <div style="background-image:none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      2 
    </div> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      3 
    </div></td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
    <div style="background:none;border:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">[root@localhost bin]</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,130,0);"># jstat -gcnew 4513</code> 
     </div> 
     <div style="background-image:none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">S0C&nbsp;&nbsp;&nbsp; S1C&nbsp;&nbsp;&nbsp; S0U&nbsp;&nbsp;&nbsp; S1U&nbsp;&nbsp; TT MTT&nbsp; DSS&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; EC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; EU&nbsp;&nbsp;&nbsp;&nbsp; YGC&nbsp;&nbsp;&nbsp;&nbsp; YGCT&nbsp; </code> 
     </div> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">54272.0 51200.0&nbsp;&nbsp;&nbsp; 0.0 40565.8&nbsp; 2&nbsp; 15 54272.0 502784.0 197950.5&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 9&nbsp;&nbsp;&nbsp; 0.198</code> 
     </div> 
    </div></td> 
  </tr> 
 </tbody> 
</table>

TT：Tenuring threshold(提升阈值)  
MTT：最大的tenuring threshold  
DSS：survivor区域大小 (KB)

**-gcnewcapacity**（新生代与其相应的内存空间的统计）

<table style="border:1px solid #C0C0C0;width:920px;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
 <tbody style="background:none;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
  <tr style="background:none;border-top:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;color:rgb(175,175,175);"> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      1 
    </div> 
    <div style="background-image:none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      2 
    </div> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      3 
    </div></td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
    <div style="background:none;border:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">[root@localhost bin]</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,130,0);"># jstat -gcnewcapacity 4513</code> 
     </div> 
     <div style="background-image:none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">NGCMN&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; NGCMX&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; NGC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; S0CMX&nbsp;&nbsp;&nbsp;&nbsp; S0C&nbsp;&nbsp;&nbsp;&nbsp; S1CMX&nbsp;&nbsp;&nbsp;&nbsp; S1C&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; ECMX&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; EC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; YGC&nbsp;&nbsp; FGC </code> 
     </div> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">84480.0&nbsp; 1349632.0&nbsp;&nbsp; 913408.0 449536.0&nbsp; 54272.0 449536.0&nbsp; 51200.0&nbsp; 1348608.0&nbsp;&nbsp; 502784.0&nbsp;&nbsp;&nbsp;&nbsp; 9&nbsp;&nbsp;&nbsp;&nbsp; 0</code> 
     </div> 
    </div></td> 
  </tr> 
 </tbody> 
</table>

NGC:当前年轻代的容量 (KB)  
S0CMX:最大的S0空间 (KB)  
S0C:当前S0空间 (KB)  
ECMX:最大eden空间 (KB)  
EC:当前eden空间 (KB)

**-gcold**（统计老年代行为）

<table style="border:1px solid #C0C0C0;width:920px;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
 <tbody style="background:none;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
  <tr style="background:none;border-top:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;color:rgb(175,175,175);"> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      1 
    </div> 
    <div style="background-image:none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      2 
    </div> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      3 
    </div></td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
    <div style="background:none;border:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">[root@localhost bin]</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,130,0);"># jstat -gcold 4513</code> 
     </div> 
     <div style="background-image:none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;&nbsp;&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">PC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; PU&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; OC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; OU&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; YGC&nbsp;&nbsp;&nbsp; FGC&nbsp;&nbsp;&nbsp; FGCT&nbsp;&nbsp;&nbsp;&nbsp; GCT&nbsp;&nbsp; </code> 
     </div> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">51712.0&nbsp; 51575.1&nbsp;&nbsp;&nbsp; 168448.0&nbsp;&nbsp;&nbsp;&nbsp; 67239.6&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 9&nbsp;&nbsp;&nbsp;&nbsp; 0&nbsp;&nbsp;&nbsp; 0.000&nbsp;&nbsp;&nbsp; 0.198</code> 
     </div> 
    </div></td> 
  </tr> 
 </tbody> 
</table>

**-gcoldcapacity**（老年代与其相应的内存空间的统计）

<table style="border:1px solid #C0C0C0;width:920px;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
 <tbody style="background:none;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
  <tr style="background:none;border-top:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;color:rgb(175,175,175);"> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      1 
    </div> 
    <div style="background-image:none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      2 
    </div> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      3 
    </div></td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
    <div style="background:none;border:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">[root@localhost bin]</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,130,0);"># jstat -gcoldcapacity 4513</code> 
     </div> 
     <div style="background-image:none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;&nbsp;&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">OGCMN&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; OGCMX&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; OGC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; OC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; YGC&nbsp;&nbsp; FGC&nbsp;&nbsp;&nbsp; FGCT&nbsp;&nbsp;&nbsp;&nbsp; GCT&nbsp;&nbsp; </code> 
     </div> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;&nbsp;&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">168448.0&nbsp;&nbsp; 2699264.0&nbsp;&nbsp;&nbsp; 168448.0&nbsp;&nbsp;&nbsp; 168448.0&nbsp;&nbsp;&nbsp;&nbsp; 9&nbsp;&nbsp;&nbsp;&nbsp; 0&nbsp;&nbsp;&nbsp; 0.000&nbsp;&nbsp; 0.198</code> 
     </div> 
    </div></td> 
  </tr> 
 </tbody> 
</table>

**-gcpermcapacity**（永久代与其相应内存空间的统计）

<table style="border:1px solid #C0C0C0;width:920px;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
 <tbody style="background:none;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
  <tr style="background:none;border-top:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;color:rgb(175,175,175);"> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      1 
    </div> 
    <div style="background-image:none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      2 
    </div> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      3 
    </div></td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
    <div style="background:none;border:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">[root@localhost bin]</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,130,0);"># jstat -gcpermcapacity 4513</code> 
     </div> 
     <div style="background-image:none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">PGCMN&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; PGCMX&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; PGC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; PC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; YGC&nbsp;&nbsp; FGC&nbsp;&nbsp;&nbsp; FGCT&nbsp;&nbsp;&nbsp;&nbsp; GCT&nbsp;&nbsp; </code> 
     </div> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">21504.0&nbsp;&nbsp;&nbsp; 83968.0&nbsp;&nbsp;&nbsp; 51712.0&nbsp;&nbsp;&nbsp; 51712.0&nbsp;&nbsp;&nbsp;&nbsp; 9&nbsp;&nbsp;&nbsp;&nbsp; 0&nbsp;&nbsp;&nbsp; 0.000&nbsp;&nbsp;&nbsp; 0.19</code> 
     </div> 
    </div></td> 
  </tr> 
 </tbody> 
</table>

**-printcompilation**（hotspot编译方法统计）

<table style="border:1px solid #C0C0C0;width:920px;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
 <tbody style="background:none;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
  <tr style="background:none;border-top:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;color:rgb(175,175,175);"> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      1 
    </div> 
    <div style="background-image:none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      2 
    </div> 
    <div style="background:rgb(244,244,244) none;border-width:0px 2px 0px 0px;border-right-style:solid;border-right-color:rgb(108,226,108);line-height:1.8em;text-align:right;vertical-align:baseline;min-height:auto;">
      3 
    </div></td> 
   <td style="border-color:#C0C0C0;border-collapse:collapse;background:none;line-height:1.1em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;font-size:12px;min-height:auto;"> 
    <div style="background:none;border:0px;line-height:1.1em;vertical-align:baseline;min-height:auto;"> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">[root@localhost bin]</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,130,0);"># jstat -printcompilation 4513</code> 
     </div> 
     <div style="background-image:none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">Compiled&nbsp; Size&nbsp; Type Method</code> 
     </div> 
     <div style="background:rgb(244,244,244) none;border:0px;line-height:1.8em;vertical-align:baseline;min-height:auto;"> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;">&nbsp;&nbsp;&nbsp;</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">1261&nbsp;&nbsp; 1261&nbsp;&nbsp;&nbsp; 1 java</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">/util/concurrent/ScheduledThreadPoolExecutor</code> 
      <code style="white-space:pre-wrap;background:none;border:0px;line-height:1.8em;vertical-align:baseline;font-family:Consolas, 'Bitstream Vera Sans Mono', 'Courier New', Courier, monospace;min-height:auto;color:rgb(0,0,0);">$DelayedWorkQueue take</code> 
     </div> 
    </div></td> 
  </tr> 
 </tbody> 
</table>

Compiled：被执行的编译任务的数量  
Size：方法字节码的字节数  
Type：编译类型  
Method：编译方法的类名和方法名。类名使用"/" 代替 "." 作为空间分隔符. 方法名是给出类的方法名. 格式是一致于HotSpot - XX:+PrintComplation 选项