20050610: multiple pqacts with gempak and mcidas

>From:  Clint Rowe <address@hidden>
>Organization:  University of Nebraska Geosciences
>Keywords:  200506101653.j5AGrJZu018909 LDM ldm-mcidas McIDAS

Hi Clint,

>I'm slowly doing some upgrades to gempak and ldm this summer and
>was thinking that having multiple pqacts sounds like a good
>idea.  Chiz has that set up for gempak, so I can do that easily,
>but I'm wondering how I go about incorporating the McIDAS actions
>into that structure.

I setup machines with both McIDAS and GEMPAK all of the time.  What I
do/have people do is put the McIDAS and ldm-mcidas actions into the
~ldm/etc/pqact.conf pattern-action file.  Since the McIDAS-XCD and
ldm-mcidas actions do not use CONDUIT, NEXRAD2, DIFAX, GEM, NOGAPS, and
NGRID streams, you can setup an 'exec' line that looks like:

exec "pqact -f ANY-CONDUIT-DIFAX-GEM-NEXRAD2-NGRID-NOGAPS etc/pqact.conf"

>Here's the setup for gempak (I'm sure you know this, but I'm
>including it for my reference; also, I'm not getting CRAFT,
>so I can ignore those):
>
>exec "pqact -f ANY-NNEXRAD-CRAFT-NIMAGE etc/pqact.gempak_decoders"'
>exec "pqact -f WMO etc/pqact.gempak_nwx"'
>exec "pqact -f MCIDAS|NIMAGE etc/pqact.gempak_images"'
>exec "pqact -f NNEXRAD|WSI|FNEXRAD etc/pqact.gempak_nexrad"'
>exec "pqact -f CRAFT -p BZIP2/K[A-D] etc/pqact.gempak_craft"'
>exec "pqact -f CRAFT -p BZIP2/K[E-K] etc/pqact.gempak_craft"'
>exec "pqact -f CRAFT -p BZIP2/K[L-R] etc/pqact.gempak_craft"'
>exec "pqact -f CRAFT -p BZIP2/K[S-Z] etc/pqact.gempak_craft"'
>
>Since McIDAS has actions for feedtypes MCIDAS, DDPLUS|IDS, HRS,
>NLDN, FSL2, and FNEXRAD do I need to split those actions up and 
>add them to the specific gempak.pqact above (e.g., take the McIDAS
>actions for DDPLUS|IDS and HRS and put them in etc/pqact.gempak_nwx
>or should I have a separate invocation of pqact with the necessary
>feedtypes with a pqact.conf file specifically for McIDAS).

I would leave the McIDAS and ldm-mcidas actions either in the generic
pqact.conf file or a file tailored for each.  Here is one idea:

exec "pqact -f WMO etc/pqact.mcidas_xcd"
exec "pqact -f NLDN|FSL2|UNIWISC etc/pqact.ldm-mcidas"

>There are at least two issues here:

>1) what's best from a machine resource point of view

We find that machines run "better" (i.e., process all of the data
without delay) when actions are segmented into individual pqact.conf
files acted upon by individual pqact invocations.  If there is not much
for the pqact to do, it doesn't add an excessive burden to the
machine's resources.

>2) what's best from a maintenance point of view

I think that Chiz's approach is the best.  I am considering doing the
same thing as he has done in including a script in my next McIDAS
release that creates a McIDAS-XCD-specific pqact.conf file and tells
the user what to add to ~ldm/etc/ldmd.conf.  If I get to it, I will do
the same for the next ldm-mcidas release.

>(i.e., how do I keep my little brain from exploding
>as I keep things working)?

That may be impossible ;-)

Hey, when are you next coming to Boulder?

Cheers,

Tom
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