Re: [PATCH] Recent VM fiasco - fixed

From: Juan J. Quintela (
Date: Wed May 10 2000 - 20:04:37 EST

>>>>> "linus" == Linus Torvalds <> writes:

linus> Which makes the whole process much more streamlined, and makes the numbers
linus> more repeatable. It also fixes the problem with dirty buffer cache data
linus> much more efficiently than the kflushd approach, and mmap002 is not a
linus> problem any more. At least for me.

linus> [ I noticed that mmap002 finishes a whole lot faster if I never actually
linus> wait for the writes to complete, but that had some nasty behaviour under
linus> low memory circumstances, so it's not what pre7-9 actually does. I
linus> _suspect_ that I should start actually waiting for pages only when
linus> priority reaches 0 - comments welcomed, see fs/buffer.c and the
linus> sync_page_buffers() function ]

        I have done my normal mmap002 test and this goes slower than
ever, it takes something like 3m50 seconds to complete, (pre7-8 2m50,
andrea classzone 2m8, and 2.2.15 1m55 for reference). I have no more
time now to do more testing, I will continue tomorrow late. My
findings are:

real 3m41.403s
user 0m16.010s
sys 0m36.890s

It takes the same user time than anterior versions, but the system
time has aumented a lot, it was ~10/12 seconds in pre7-8 and around 8
in classzone and 2.2.15.

Later, Juan.

In theory, practice and theory are the same, but in practice they 
are different -- Larry McVoy

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