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Altera_Forum
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20 years ago

BogoMIPS

Iam able to get a maximum of 24.67 BogoMIPS with NIOSII on Cyclone 1C20 Eval Board running at 50 MHz (NIOS II/f - with maximum CPU features) Is it possible to get more MIPS using NIOS II. If ...
Altera_Forum's avatar
Altera_Forum
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20 years ago

BogoMIPS should not be confused with any real measure of processing power.<div class='quotetop'>QUOTE </div>

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BogoMips are Linus&#39;s invention. The kernel (or was it a device driver?) needs a timing loop (the time is too short and/or needs to be too exact for a non-busy-loop method of waiting), which must be calibrated to the processor speed of the machine. Hence, the kernel measures at boot time how fast a certain kind of busy loop runs on a computer. "Bogo" comes from "bogus", i.e, something which is a fake. Hence, the BogoMips value gives some indication of the processor speed, but it is way too unscientific to be called anything but BogoMips.[/b]

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For more information on BogoMIPS, see the bogomips mini-howto (http://www.tldp.org/howto/bogomips/x78.html).

The code that generates the BogoMips value can be found in <Nios II installation directory>/bin/eclipse/plugins/com.microtronix.nios2linux.kernel_0.1.5/linux-2.6.x/init/main.c

Dennis Scott

Microtronix Datacom Ltd.