我通过在下面添加以下行来设置tomcat 7的堆大小 catalina.sh

export CATALINA_OPTS="-Xms512m -Xmx1024m"

然后停止并启动了tomcat。但是当尝试使用命令jmap -heap获取堆大小时，我可以注意到内存没有变化：

Heap Configuration:
   MinHeapFreeRatio = 40
   MaxHeapFreeRatio = 70
   MaxHeapSize      = 526385152 (502.0MB)
   NewSize          = 1048576 (1.0MB)
   MaxNewSize       = 4294901760 (4095.9375MB)
   OldSize          = 4194304 (4.0MB)
   NewRatio         = 2
   SurvivorRatio    = 8
   PermSize         = 16777216 (16.0MB)
   MaxPermSize      = 67108864 (64.0MB)

Heap Usage:
PS Young Generation
Eden Space:
   capacity = 99352576 (94.75MB)
   used     = 9643144 (9.196418762207031MB)
   free     = 89709432 (85.55358123779297MB)
   9.705982862487632% used
From Space:
   capacity = 4063232 (3.875MB)
   used     = 0 (0.0MB)
   free     = 4063232 (3.875MB)
   0.0% used
To Space:
   capacity = 5177344 (4.9375MB)
   used     = 0 (0.0MB)
   free     = 5177344 (4.9375MB)
   0.0% used
PS Old Generation
   capacity = 37748736 (36.0MB)
   used     = 21889008 (20.874984741210938MB)
   free     = 15859728 (15.125015258789062MB)
   57.98606872558594% used
PS Perm Generation
   capacity = 60948480 (58.125MB)
   used     = 31496008 (30.03693389892578MB)
   free     = 29452472 (28.08806610107422MB)
   51.67644541750672% used

请指教。