[daip] Slow TVBOX

[Eric Greisen]

Laura writes:

 > I've recently upgraded my computer from Redhat 9 to Fedora Core 6, and 
 > with it I changed from 31DEC05 to 31DEC06 AIPS. Since I've been using 
 > the new AIPS my tv cursor when I run TVBOX has been extremely slow and 
 > I've been trying to figure out what the problem is. I noticed in the old 
 > daip mailing list archives, a thread entitled:
 > [daip] Extremely slow TV based tasks 
 > <http://listmgr.cv.nrao.edu/pipermail/daip/2004-November/007190.html>
 > which seems to describe my problem - even the fact that TVBOX works fine 
 > maybe the first time I run it, but is terrible after that.
 > 
 > Unfortunately I couldn't find the eventual resolution to that thread! 
 > How did you fix the problem there?
 > 

Our problem is that we cannot remember exactly what was done.  I did
ask our system experts what they did and they have not yet remembered
any one specific thing.  The problem does seem to be resolved here
however.  The problem was much worse on older, slower computers but
was maddening on the new fast one they gave me a year ago.

The issue has to do with the system simply neglecting to process
interupts which are necessary to run X-Windows code.  There are timing
parameters all over the system that control both kernel handling of
interupts and X Windows matters specifically.  I will see if I can
dredge up their memories of the matter but you may have to experiment
as well.  I do not run AIPS "in anger" (i.e. on lots of data) much of
the time and so become most acutely aware of such issues only in those
interesting periods when I do get to reduce data.  The problem went
away between two such but why or exactly when I cannot say.

Eric Greisen