----- Original Message -----
Sent: Tuesday, November 21, 2000 7:51
AM
Subject: RE: emulating RDTSC
A second thread would be a bad idea in my opinion. A constant
counting
busy thread would slow the system down by an
unacceptable rate compared
to what you get from it.
Also the assumption that both threads may get
about
the same amount of cpu cycles is wrong. The emulator will block
on I/O, if for example the guest read an sector from the
hdimage.
Therefore the results will be very
inacurate.
And Mark, you are right. The counter cannot be set or cleared.
(I thought
CLTS will do it, but that the task switch
flag reset inside the flags)
Norbert
-----Original Message-----
From: Nick
Behnken [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, November 21, 2000 2:36 PM
To: [EMAIL PROTECTED]
Subject: Re: emulating
RDTSC
Ramon, I'm not arguing with you, cause I know your right.. But
can you
explain why a thread wouldn't work? My
assumption was that the thread would
get an equal
amount of cpu time as the emulator thread, which I would think
would make is someone accurate.. maybe its just a brain block
on my part ;-)
Nick
----- Original Message -----
From:
"Ramon van Handel" <[EMAIL PROTECTED]>
To:
<[EMAIL PROTECTED]>
Sent: Tuesday, November 21,
2000 7:17 AM
Subject: Re: emulating RDTSC
> >Why emulating it anyway ? I don't think plex86 makes
any sense on
> >"none pentium class" PC's
(performance!). Therefore the instruction
>
>could be executed directly. However I'm not sure if a counter reset
may
> >cause any harm to the (Linux)host.
>
> The time in the guest runs
faster than the "real" time, because we have to
>
correct for the amount of time spent in different processes (after all,
the
> plex86 process is just one
process on your linux system). For the same
>
reason, running an "RDTSC thread" makes no sense (it wouldn't make much
sense
> anyway, because you might
as well use the host timing functions.) There
is
some
> timing code in place already in the VM,
which is where this needs to be
handled.
>
> -- Ramon
>
> PS still coding & active &
stuff, but a bit flummoxed by the huge amount
of
> emails I'm suddenly getting... can't we
split the lists or something?
>
>
>
>
>
>
