I've just go the hint to do

    echo 3 > /proc/sys/vm/drop_caches

via private mail. Tried that, but does not change a thing.

I'm now in a new situation: I did *not* do a backup, but still
have ~800M of slab usage. I'm trying to compile a kernel now without
running out of memory (not so easy, if you are used to do make -j)

Attached are the latest figures from my (still) running system.

Cheers,

Nico

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