[daip] Re: fits file

[Eric Greisen]

Katherine Blundell writes:

 > I'm having problems coaxing my Mac to give me an aips tv (not aware  
 > that I had changed anything since last using it...) - any thoughts?

   I suspect a system update...

 > ?XAS: ** TrueColor FOUND!!!
 > XAS: ***  Using shared memory option for speed ***
 > XAS: Using screen width height 1670 950, max grey level 255
 > Shared memory id failure: Invalid argument

>From our aips manager FAQ page:


 Shared memory id failure: Invalid Argument

    If you see this when the system is trying to fire up the AIPS TV
(XAS) on a Solaris system, then your X11 display does not support more
than the default of 1 Megabyte maximum for shared memory segment. If
your monitor displays 1280x1024 or larger, the sizes of the shared
memory segments XAS wants will exceed a Megabyte. Solution: have your
sysadmin edit /etc/system and put this line somewhere near the end:


        set shmsys:shminfo_shmmax=8388608

    While there, you may want to also add these if you have more than
64 Mbytes of real memory:

        set ufs:ufs_HW=6291456
        set ufs:ufs_LW=4194304
        set priority_paging=1 

    Only add the last one if you are running Solaris 7 or later. These
three settings will boost your overall AIPS performance.

    If you see this on a Mac, congratulations; you have one of the
larger display screens. The default Mac system limits shared memory
pages to 4 Mbytes. When XAS starts it tells you that it is making a
screen x pixels by y pixels. The memory you will need is at least 4 x
y bytes. For the new large screens this is more than 8 Mbytes. On
Panther systems (X 10.3), you can change this limit by changing (as
root or admin) the rc file in /etc, adjusting the kern.sysv.shm* line
to

         #Setting the shared memory to something a bit more reasonable.
            sysctl -w kern.sysv.shmmax=10485760
            sysctl -w kern.sysv.shmmin=1
            sysctl -w kern.sysv.shmmni=32
            sysctl -w kern.sysv.shmseg=8
            sysctl -w kern.sysv.shmall=4096
         

    If you are really lucky and have a 30-inch screen (2550 by 1500
pixels) then you will have to make the shmmax line even larger

            sysctl -w kern.sysv.shmmax=16777216

On older Jaguar systems (X 10.2), you can change this limit by
changing the SystemTuning file in
 
            /System/Library/StartupItems/SystemTuning

Look for the lines

            sysctl -w kern.sysv.shmmax=4194304
            sysctl -w kern.sysv.shmall=1024
         
Change the 4194304 to 10485760 (for 10 Mbytes) and change the 1024 to
4096 (allows 16 Megabytes). You must then re-boot the computer to have
these changes take effect

Cheers,

Eric