PROBLEM: ramfs causes system hang when swapping

From: Norbert Nemec (
Date: Mon Feb 26 2001 - 16:03:38 EST


seems like ramfs lets the system hang when swapping is involved.

I have a ramfs mounted as /tmp. When I create a large file:

    dd if=/dev/zero of=/tmp/xxx bs=1024K count=200
(with 128M RAM), the complete system comes to a halt. Hitting keys does not do
anything anymore, console switching still works, but all other processes come
to a halt as well. SysRq still works and by doing a 'saK', I can kill the dd
process - afterwards, everything is fine again.

Same thing anytime I write large amounts of data to the ramfs.

Now today I even had that problem without writing anything to /tmp: running a
compilation that creates one process sized ~100M, suddenly everything froze the
same way as described above. Later a unmounted the ramfs and everything worked

B.t.w.: Apart from this bug, ramfs really is a great thing. Mounting it to /tmp
speeds up a number of tasks significantly! (p.e. browsing into archives with
mc, which uses temporary files heavily.) IMO, that method should be propagated
much more!


-- ______________________________________________________
--          To Him, even that machine here has to obey...
-- _________________________________Norbert "Nobbi" Nemec
-- Hindenburgstr. 44  ...  D-91054 Erlangen  ...  Germany
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This archive was generated by hypermail 2b29 : Wed Feb 28 2001 - 21:00:12 EST