memory leak?

[Måns Rullgård]

I noticed that doing lots or file accesses causes the used memory to
increase, *after* subtracting buffers/cache. Here is an example:

$ free
             total       used       free     shared    buffers     cached
Mem:        773776      30024     743752          0       1992      10424
-/+ buffers/cache:      17608     756168
Swap:        81904          0      81904
$ du > /dev/null
$ free
             total       used       free     shared    buffers     cached
Mem:        773776      78008     695768          0      26328      10472
-/+ buffers/cache:      41208     732568
Swap:        81904          0      81904

Here 24 MB of memory have been used up. Repeating the du seems to have
little effect. This directory has ~3200 subdirs and 13400 files.

After a few hours use about 200 MB are used, apperently for
nothing. Killing all processed and unmounting file systems doesn't
help.

Is this a memory leak? I get the same results with ext2, ext3,
reiserfs and nfs.

-- 
Måns Rullgård
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