Physical Memory Utilization for Linux monitor issue

Hi all,

I just install Application Manager (AP) 7.3 in Windows XP for testing and monitor a linux server. I use "telnet" method to get information from Red Hat Linux server. I find that the value for Physical Memory Utilization is different from the value getting directly in Linux server ( run command "free -m" ). The used memory should be 340M but in AP just show 118M ( I don't capture the screen). So I wonder how Application Manager generate the result for Physical Memory Utilization. Please help to verify it. Thanks in advance.

The value get from Red Hat Linux
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[root@xxxx ~]# free -m
total used free shared buffers cached
Mem: 375 340 34 0 19 203
-/+ buffers/cache: 118 257
Swap: 0 0 0