[clug] Appropriate language for a task...

Duncan Roe duncan_roe at acslink.net.au
Sat Sep 6 23:47:48 GMT 2008

Don't forget the realtime clock (/dev/rtc) for timing information. See
Documentation/rtc in your linux source directory

Cheers ... Duncan.

On Mon, Sep 01, 2008 at 05:26:34PM +1000, Robert Edwards wrote:
> You can recompile the kernel with the system clock running at 1kHz,
> if you need to be able to schedule events to occur with millisecond
> accuracy (no guarantee that the kernel will actually run them when
> you want, but most of the time, on an unloaded machine, it will).
> Language of choice: C, with xlib etc. for your User Interface - can't
> go wrong with that...
> More reasonably, I would separate out the UI from the bit that needs
> millisecond accuracy and run them on separate boxes with a UDP
> messaging system running over an unloaded network between them.
> You can write your UI in whatever takes your fancy on the machine
> doing the UI.
> Definitely don't connect the machine requiring millisecond timing
> to the Internet, or any network without a good firewall and no
> broadcasting going on (use static ARP etc.). Network interfaces
> are a great source of non-deterministic load. Also, avoid disks
> and any journalling file-system - use UDP and/or syslog to send
> data to another machine for capture and storage. Also, no graphics
> and especially no mouse! (or keyboard, if possible). And no USB!
> Cheers,
> Bob Edwards.
> David Tulloh wrote:
> >You can't get timing guarantees on a modern PC without a lot of effort
> >(have a look at the realtime Linux work).  The PC just isn't designed
> >for it, garbage collection is a fairly small issue compared to the
> >scheduler.
> >
> >That said, a millisecond is a large time window to a processor so you
> >should be able to get away without too much work depending on how
> >critical the timing accuracy is to your application.
> >
> >
> >David
> >
> >jm wrote:
> >>You could turn GC off when needed.
> >>
> >>Jeff.
> >>
> >>Jason wrote:
> >>>Never had to do something with millisecond accuracy though so don't
> >>>know how well an interpreted language will cope with that, never know
> >>>when those pesky garbage collectors are going to wake up or so I
> >>>remember being told many years ago, might be fixed as an issue by now.
> >>>
> >>>
> >
> --
> linux mailing list
> linux at lists.samba.org
> https://lists.samba.org/mailman/listinfo/linux

 Please avoid sending me Word or PowerPoint attachments.
 See http://www.gnu.org/philosophy/no-word-attachments.html

More information about the linux mailing list