Re: Is it possible to get 100microsecond timer resolution using the CPU TSC?

On Apr 23, 11:18 pm, avi01 <kurup.avin...@xxxxxxxxx> wrote:
Hi All,
I'm using the 2.6.24.3 kernel and I need to write a module
that runs a function every 100 microseconds (intervals SHOULD occur @
100 microsecond intervals).
tried using the HPET (high precision event timer), but it;s
not present on my main board.
Now I need to know if it's possible to use the x86 Time
stamp counter for the above application, or can I use the ACPI timer?

Please help me!!!
Thanking U.

Avinash.

How reliably do you want the interval to be (eg: is it ok if the
interval occasionally becomes 101uS, how about 110uS) ?
If the variations above are ok, you probably can getaway with a low
latency kernel (as I could remember default kernel time slices were
100uS anyway). For it to be more consistent I would recommend using
the "Preemptible kernel" option.
However you may have to use a hardware timer interrupt if you want the
timing to be exactly at 100uS.
.

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