Case study: "Large?" labview programs flooded with different VIT's

Case study: "Large?" labview programs flooded
with different VIT's
Type of application:
Computer with loads of individual hardware connected or other software (either
onsite (different buses) or offsite (Satelite/GSM/GPRS/radio etc.).
Hardware
description: little data "RPM" but communications to all devices are intact.
More "RPM" when many VITs are involved.
Size: 1000+
VITS in memory (goal). Total software has been tested and simulated with 400.
I'm posting
this post after reading this thread (and actually I cant sleep and am bored as
hell).
Note: I do
not use LVOOP (but sure post OOP examples, am starting to learn more and more
by the day.)
Things I
will discuss are:
Case 1: Memory usage using a plugin
architecture
CASE 2: memory usage using VITs (!)
CASE 3: updating datastructures:
CASE 4: shutdown of the whole system
CASE 5: stability & heath monitoring
CASE 6: Inifiles
CASE 7: When the hardware is getting crappy
Total
application overview:
We have a
main application. This main application is mainly empty as hell, and only holds
a plugin functionality (to register and administer plugins) and holds an
architecture that holds the following items:
Queue state
machine for main application error handling
Queue state
machine for status messages
Queue state
machine for updating virtual variables
Event state
machine for GUI
Some other
stuff
Other
global functionality is:
User
logins, user configurations and unique access levels
Different
nice tools like the good old BootP and other juicy stuff
Supervision
of variables (like the NI tag engine, but here we have our own datastructures)
Generation
of virtual variables (so that the user can configure easy mathematical
functions and combining existing tags)
Licensing
of plugins (hell we free-lance programmers need some money to don't we?)
Handles
all communication between plugins themselves, or directly to a plugin or vice
versus.
And now we don't
talk about that (or marketing) the main application .
Message Edited by Corny on 01-20-2010 08:52 AM

CASE 3: updating datastructures:
As we do NOT use clusters here (that would
just be consuming) we only use an 1D array of data that needs to be updated in
different functional globals. If the the number of VITS exceeds so that the
updating of this datastructures becomes the bottleneck, this would cause
delays. And since in this example we use 250 serial interfaces (lol) we do not
want to disrupt that by any delays. When this happends, does anyone know a good
solution to transfer data?
A thought:
perhaps sending it down to the plugin and let the plugin handle it, this should
save some time, but then again if more VITs are added again this would become a
bottleneck and the queue would fill up after a while unable to process it fast
enough. Any opinions?
CASE 4: shutdown of the whole system
Lets say we
want to close it all down, but the VITs need perhaps to do some shutdown
procedure towards the hardware, that can be heavy.
If we ask
them to shutdown all together we can use an natofier or userevent to do this
job. Well, what happends next is that the CPU will jump to the roof, and well
that can only cause dataloss and trouble. The solution here was to let the
plugin shut them all down one by one, when one has been shutdown, begin at the
next. Pro; CPU will not jump to the moon. Con's: shutdown is going to take a
while. Be ready with a cup of coffee.
Also we
want the main application not to exit before we exit. The solution above solved
this as the plugin knows when all have been shut down, and can then shut itself
down. When all plugins are shutdown - the application ends.
Another
solution is to use rendovous (arg cant spell it) and only shut the system down
when all rendezvous have met.
CASE 5: stability & heath monitoring
This IS
using a lot of memory. How to get it down. And has anyone experienced any
difficulties with labview using A LOT of memory? I want to know if something
gets corrupt. The VITs send out error information in case, but what if
something weird happens, how can I surveillance all the VIT's in memory to know
one is malfunctioning in an effective way/code (as backup
solution so the application knows
something is wrong?
CASE 6: Inifiles
Well, we
all like them. Even if XML is perhaps more fahionally. Now Ive runned some
tests on large inifiles. And the labview Inifile functions use ages to parsing
all this information. Perhaps an own file structure in binary format or
something would be better? (and rather create an configuration program)?
CASE 7: When the hardware is getting crappy:
Now what if
the system is hitting the limit and gradually exceeds the hardware req. of the
software. What to do then (thinking mostly of memory usage)? Needing to install
it on more servers or something and splitting configurations? Is that the best
way to solve this? Any opinions?
Wow. Time for a coffee cup. Impressive if someone
actually read all of this. My goal is to reach the 1000 VIT mark.. someday.. so
any opinions, and just ask if something unclear or other stuff, Im open for all
stuff, since I see the software will hit a memory barrier someday if I want to
reach that 1000 mark hehe

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We have the following problem:
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PS: i attached the controller part of my program and the overall program
desperate happyguy......
Happy guy
~ currently final year undergraduate in Electrical Engr. Graduating soon! Yes!
~ currently looking for jobs : any position related to engineering, labview, programming, tech support would be great.
~ humber learner of LabVIEW lvl: beginner-intermediate
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hi xseadog
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