HPET vs other timers

[Poul-Henning Kamp]

In message <20070602194151.GA1604 at rot13.obsecurity.org>, Kris Kennaway writes:

>> Anyone able to speculate why though?  HPET only reads 32 bits from a
>> memory mapped region.  No locking or other requirements.  ACPI_timer
>> does multiple IO ops, which according to bde@ are much slower than
>> memory reads.  

HPET needs to do metastability mitigation and is not "just a read
from a memory mapped region".

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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