Hi,

I have a program that continuously writes multiple streams into files on
the disk. I'm seeing a strange phenomenon -- the CPU load is in the
single digits (both "user" and "system"), however the load average is
very high, and the system is very unresponsive. The disk is running in
DMA mode so that shouldn't be a problem. I thought maybe it's the high
number of system calls per second that causes high context switching
overhead, but the same program can also read those streams from the
files instead of writing, and in that case the load average stays near
zero, with the same number of system calls.

I'm using 2.4.20 with the ext3 filesystem, tried both in data=ordered
and data=writeback modes. Do you think it may be a filesystem problem?

And in any case, I'd really like to understand how it's possible to have
very light CPU load and a high load average. If I understand correctly,
the latter is the average of the number of processes ready to run at any
given moment. In that case, why is the CPU load so low -- why aren't
they running?


-- 
Alex Shnitman <[EMAIL PROTECTED]>
http://www.hectic.net/   UIN 188956
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