Re: High load average on disk I/O on 2.6.17-rc3

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Russell King wrote:
Why do you think that?  exim uses the load average to work out whether
it's a good idea to spawn more copies of itself, and increase the load
on the machine.

Unfortunately though, under 2.6 kernels, the load average seems to be
a meaningless indication of how busy the system is from that point of
view.

Having a single CPU machine with a load average of 150 and still feel
very interactive at the shell is extremely counter-intuitive.

It's even worse: load average used to mean the number of runnable processes + number of processes waiting on disk or NFS I/O to complete, a fairly bogus measure as you have noted, but with the aio interfaces one can issue enormous amounts of I/O without it being counted in the load average.

To make such decisions real, one needs separate counters for cpu load and for disk load on the devices one is actually using.

--
error compiling committee.c: too many arguments to function

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