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RE: computational program spending lot of time in kernel

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• Reply: Greg Lindahl: "RE: computational program spending lot of time in kernel"

> I have got a problem: I have tried to run old large Fortran code
> (compiled with fort -fast) and have noticed that it is unexpectedly slow.
> Closer investigation revealed that it spends more than 50% of CPU time in
> kernel.

If I understand things correctly, with the -fast flag, you won't ever trap
to the kernel for exceptional floating point operations.

I'm not so sure that all Alpha kernels had a correct accounting of user vs.
system time. But there could be other reasons it is in the kernel. Try using
"strace" to see if it's doing weird system calls.

-- g

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