cpu0 at mainbus?
cpu* at mainbus?
Several processor models have additional features that extend their base
functionality, such as power and frequency control or thermal monitoring.
return the current operating frequency of the processor (on some processors
this value may be an approximation). If possible, speed may be adjusted by
altering hw.setperf from 0 to 100, representing percentage of maximum speed.
There are several possible implementations for setperf, all transparent to the
user. In systems with more than one control capability, they are preferred in
the order given.
- Found on Transmeta Crusoe processors, offers frequency
scaling with numerous positions. The processor dynamically adjusts
frequency in response to load, the setperf value is interpreted as the
- Enhanced SpeedStep found on Intel Pentium M processors,
offers frequency scaling with numerous positions.
- Found on some Intel Pentium 3 and newer mobile chips, it is
capable of adjusting frequency between a low and high value. Only enabled
on some chipsets.
- Thermal Control Circuit found on Intel Pentium 4 and newer
processors, adjusts processor duty cycle in 12.5 percent increments.
- Found on various AMD processors. Currently only supports a
limited set of models in the K6, K7, and K8 families.
The presence of extended instruction sets can be determined by sysctl machdep.
- Supports the fxsave instruction.
- Supports the SSE instruction set.
- Supports the SSE2 instruction set.
- Support the VIA AES encryption instruction set. If this is
libcrypto EVP AES functions will
automatically use this support.
hw.sensors.cpu*.temp0 will return the current temperature reported by the
Due to the way in which thermal information is reported on Intel processors, the
temperature may be off by exactly +/-15 degrees C.
For multiprocessor kernels with more than one CPU sensor, processors will report
identical temperatures since the temperature is taken from the processor
running the sensors update.