Memory not free after kill?

Hi, folks:

I'm using uClinux (2.4.19) for my project. What I want to do is to kill a few processes to free up memory before a memory-hungry process can be run. What I discover is, not much memory is freed after kill -9.

Please refer the bottom for detail info.

I was expecting the available memory is the same before and after kill BoA. Can anyone explain to me why the memory is gone?

BoA: ls -l

-rwxr-xr-x 1 0 0 113668 Jan 1 00:00 boa

1. Before I run BoA, output of "cat meminfo"

total: used: free: shared: buffers: cached: Mem: 12963840 4308992 8654848 0 573440 585728 Swap: 0 0 0 MemTotal: 12660 kB MemFree: 8452 kB MemShared: 0 kB Buffers: 560 kB Cached: 572 kB SwapCached: 0 kB Active: 812 kB Inactive: 320 kB HighTotal: 0 kB HighFree: 0 kB LowTotal: 12660 kB LowFree: 8452 kB SwapTotal: 0 kB

1. After run BoA. total: used: free: shared: buffers: cached: Mem: 12963840 5124096 7839744 0 692224 712704 Swap: 0 0 0 MemTotal: 12660 kB MemFree: 7656 kB MemShared: 0 kB Buffers: 676 kB Cached: 696 kB SwapCached: 0 kB Active: 928 kB Inactive: 444 kB HighTotal: 0 kB HighFree: 0 kB LowTotal: 12660 kB LowFree: 7656 kB SwapTotal: 0 kB

1. After BoA is killed. total: used: free: shared: buffers: cached: Mem: 12963840 5111808 7852032 0 692224 712704 Swap: 0 0 0 MemTotal: 12660 kB MemFree: 7668 kB MemShared: 0 kB Buffers: 676 kB Cached: 696 kB SwapCached: 0 kB Active: 928 kB Inactive: 444 kB HighTotal: 0 kB HighFree: 0 kB LowTotal: 12660 kB LowFree: 7668 kB SwapTotal: 0 kB SwapFree: 0 kB