Re: Privilege Levels Below User

BGB wrote:

On 6/8/2024 11:01 AM, EricP wrote:

Scott Lurndal wrote:

John Savard <quadibloc@servername.invalid> writes:

Though, the time returned by the CPUID microsecond timer is not currently the same as the one given by "TK_GetTimeUS()", where the latter effectively gives a 64-bit value (conceptually) representing the
 number of microseconds since 1/1/1970; though with the kernel currently
 assuming that its build-time is the starting time for the clock (and none of the FPGA boards support a hardware clock, and one would need internet access to use NTP, ...).

A 64-bit value in microseconds can express around +/- 300k years, which
 should be plenty.

What do you do when you need a 200 picosecond timer ?? (5GHz cycle
counter)

A 64-bit value expressed in seconds could express values relative to
the
current age of the universe, but this is likely unnecessary for most purposes, and ability to express fractions of a second is likely more useful than the ability to express the age of the universe.

Interesting factoid::
The universe is currently 10^80 Plank times old since Big Bang,
and universe will die around 10^80 years,
and there are about 10^80-10^88 particles in the universe.

Granted, one could use a 128-bit value, and have both (and in picoseconds if they wanted). But, this would be overkill.

Or, go extra overkill, and use 256 bits, to express the current age of the universe in Planck units...

160-bits will be shown to be sufficient to count Plank times.