Hi all,
I have had non-stop CPU spikes and freezes related to denormal numbers on my Pentium 4 1.6GHz laptop ever since I switch to Linux, going from kernel 2.4.18 up to 2.6.4.
The main applications which seem to be affected are Freqtweak, Jamin and Pure Data, along with a handful of LADSPA plugins, which can sometimes make my Ardour sessions a real PITA. Does everyone develop on Celerons or AMDs these days?!? ;-)
I have pursued the problem in particular with Pure Data, but have been assured that there is already denormal handling in the program... It has gotten to the point where either I find a kernel-level solution for the problem or I buy a new laptop!
Tim Blechman reported on the PD list that his denormal problems only started when he switched from SuSE to Gentoo. My suspicion is that the SuSE kernel developers either cooked up a very good patch against denormals, or they are using a proprietary Intel compiler for their kernels which somehow alleviates the problem. For my own purposes, the former is more attractive than the latter, of course.
Tim also mentioned that some P4s have a Denormals-As-Zero switch to handle the problem [although I suspect that my CPU might be too old for this feature...]. Can anyone explain how such a DAZ switch can be tested for and toggled?
Can anybody shed some light on the situation? I would hate to have to ditch a decent computer over this issue.
best wishes, Derek -- derek holzer ::: http://www.umatic.nl ---Oblique Strategy # 127: "Openly resist change"
