intel experience


    Dec 01 2006 | 10:05 pm
    hi!
    i have just made a strange experience working on an intel mini mac we use for an installation.
    i was planning to run the machine without a display connected as its output is only sound and dmx with another part of the patch doing jitter video processing of a live camera feed.
    in such a situation i use a VNC server to be able to operate the machine remotely. this works flawlessly when an actual screen is connected to the mini mac. if i unplug the screen, though, and reboot without a display the jitter performance drops from 30 fps to 5 fps.
    now, if i do the same to a PPC mini mac the same thing happens, but not quite as bad. the frame rate drops from 11 fps to 7.5 fps, so that in the end the PPC outruns the intel machine (!) which is actually 3 times as fast.
    would anyone know a way to explain this?
    as far as i understand it the intel machine does not have any dedicated video ram anymore, but uses a part of the computers memory. presumably the size of memory changes depending on the size of the display and without an actual screen there, it could be very small.
    could i fool the intel machine that there really is a nice 20 inch screen there somewhere..?
    any pointers would be appreciated!
    many thanks hiaz

    • Dec 01 2006 | 11:10 pm
      Usually the problem is with the machine not wanting to run at all, and the solution for that can sometimes be to hook a video adapter onto the machine to trick it into thinking it has a display. This seems like something different, but it's still worth a try.
      Ian
      On Dec 1, 2006, at 2:05 PM, hiaz wrote:
      > hi! > > i have just made a strange experience working on an intel mini mac > we use for an installation. > > i was planning to run the machine without a display connected as > its output is only sound and dmx with another part of the patch > doing jitter video processing of a live camera feed. > > in such a situation i use a VNC server to be able to operate the > machine remotely. > this works flawlessly when an actual screen is connected to the > mini mac. > if i unplug the screen, though, and reboot without a display the > jitter performance drops from 30 fps to 5 fps. > > now, if i do the same to a PPC mini mac the same thing happens, but > not quite as bad. > the frame rate drops from 11 fps to 7.5 fps, so that in the end the > PPC outruns the intel machine (!) which is actually 3 times as fast. > > would anyone know a way to explain this? > > as far as i understand it the intel machine does not have any > dedicated video ram anymore, but uses a part of the computers memory. > presumably the size of memory changes depending on the size of the > display and without an actual screen there, it could be very small. > > could i fool the intel machine that there really is a nice 20 inch > screen there somewhere..? > > any pointers would be appreciated! > > > many thanks > hiaz >
    • Dec 01 2006 | 11:56 pm
      On 1-dec-2006, at 23:05, hiaz wrote:
      > could i fool the intel machine that there really is a nice 20 inch > screen there somewhere..?
      HtH -jennek
    • Dec 02 2006 | 12:51 am
      I did a web-search: running OSX headless. These two might be of interest:
      The dummy adaptor idea seems rather clever and might work on a MacTel.
      (As for VNC servers imposing extreme CPU loading, I've had similar experiences under Win2K/XP in a server application (not a Max app -- this is the day job) with a VNC server taking better than 50% of a 2.8G P4 (and not related to headless ops, per se). We never resolved it, and now I wonder if it was something as silly as the monitor having been turned off!)
    • Jun 06 2007 | 6:52 pm
      On 1 Dec 2006, at 23:56, jennek geels wrote:
      > > On 1-dec-2006, at 23:05, hiaz wrote: > >> could i fool the intel machine that there really is a nice 20 inch >> screen there somewhere..? > > try this > http://tvtool.info/english/dummy_e.htm > > HtH > -jennek
      Jennek!
      This is a rather reply, but... thanks a lot for the pointer to the TV dummy.
      I have soldered up 2 yesterday and they work brilliantly!
      best hiaz