一个程序运行一段时间，内存变化如下，但是系统得字体会变成空格，也没有提示虚拟内存不足，

机器速度明显下降，求高人指点，我怀疑是虚拟内存得原因，但是又看不出来
突然间就变得字体不能显示，时间再久机器就会慢慢死掉，程序自己退出了
pu      内存使用    虚拟内存大小   进程时间   9:01开始启动程序
             16        7,048k       24,968         9:02
              25        8,028k       24,994         9:07
中间由于管理员工作，暂时无纪录
              73       12,504k       25,228         9:55
              50       19,608k       27,608        10:00
              51       20,240k       27,608        10:09
              36       20,680k       27,660        10:14
              59       21,236k       27,768        10:20
              51       21,548k       27,676        10:25
              58       21,864k       27,660        10:32
              99       22,300k       27,524        10:37
              31       23,064k       28,400        10:42
              42       23,116k       28,440        10:50
              22       23,136k       28,712        10:55
              43       15,564k       29,576        11:00
              36       17,320k       29,668        11:05
              58       17,768k       29,704        11:10
              47       18,068k       29,764        11:15
              99       18,472k       29,769        11:21
              25       18,944k       29,908        11:28
              58       19,240k       29,944        11:33
  午饭时间
              48       23,084k       31,772        12:08
              33       23,356k       31,812        12:13
              43        7,316k       31,688        12:18
              33       17,048k       32,896        12:23
              42        8,148k       32,780        12:28
              66        9,524k       33,020        12:34
              45       10,020k       33,040        12:40 
              99       10,464k       33,036        12:45
              08       10,936k       33.060        12:50
              19        8,824k       33,120        12:56
              27        7,692k       33,484        13:02 
              16        8,404k       33,496        13:07
曾经在这段时间使用查询ip功能
              25       30,036k       44,416        13:15
              25       28,680k       45,928        13:20
              50       29.084k       46,072        13:25
再次执行查询功能
              99       33,516k       48,500        13:30
              47       33,912k       48,640        13:35
              28       34,452k       48,736        13:40
第三次执行查询功能
              99       38,952k       52,964        13:46
开始全面出现屏幕乱码状态，及时退出程序约2分钟后恢复正常，系统运行速度变得很慢，约4分钟后恢复正常，重新启动时间13：51
              99        7,552k       26,088       13:53
              13       10,412k       26,428       14:01
              45       12,448k       28,140       14:08
执行过查询功能
              56       28,128k       37,508       14:18
              48        7,896k       37,712       14:24
              22        7,404k       37,852       14:29
              73        8,520k       38,064       14:35              63        7,796k       78,040       15:10
              38        8,928k       78,072       15:15              48       16,802k       77,968       15:51
15:52开始出现屏幕错误问题，左下角开始菜单点击后无下拉菜单显示，输入法输入后无任何字符显示。
              27       17,425k       78,012       15:56
15:56关闭，一切全部恢复正常，15：58重新开启程序。