This is not at all specific to ext2fs, so should be integrated elsewhere.

IRC, freenode, #hurd, 2012-04-22

<Tekk_> is there any particular reason ext2fs takes so much memory?
<Tekk_> it beats everything on my system hands down at 100 MB
<youpi> ext2fs contains the page cache
<youpi> so it's no wonder it takes memory
<youpi> it's all the mapped files
<Tekk_> any way I can cut down on that?
<Tekk_> my system only has 512 meg :/
<youpi> gnumach is supposed to automatically cut it down as needed
<youpi> what is the actual symptom that you see?
<Tekk_> youpi: 360 MB of memory usage when I'm doing nothing
<Tekk_> oh, is it just intelligent enough to cut down when I'm using more
  memory?
<youpi> Tekk_: yes
<Tekk_> awesome. I was worried :)

Actually, ext2fs doesn't contain its page cache (the virtual and physical memory counters do not take the cache size into account). But it must allocate descriptors for the cached content.