Detect if MATLAB startup.m is running on a worker - parallel-processing

A colleague has a MATLAB startup.m file that contains interactive code (it calls the command questdlg to ask him which project directory he wishes to work in).
This works fine for him when running MATLAB directly. However, he also needs to run MATLAB code in parallel, having started up a matlabpool.
When starting up, the workers in the matlabpool are running his startup.m file, getting to the questdlg and then hanging (infinitely, or until Ctrl C).
An easy solution is to just get rid of the interactive code from his startup.m, as it's not really essential.
But is there a way to detect whether this startup.m is being run by a worker starting up - something similar to isdeployed or ismcc? Then he could keep the interactive code that he finds useful, but only execute it when not starting up a worker.
The command getCurrentWorker seemed like it might be what was needed, but I believe that only works during the execution of a task, rather than at startup.

You could use the usejava function to see if the interactive desktop is running, which is probably a good enough approximation unless you frequently use -nodesktop mode.
if usejava('desktop')
questdlg(...);
end

Take a look at labindex and, failing that, labSend and labReceive.

At least for my R2014b,
isempty(getCurrentWorker)
seem to do the job:
>> getCurrentWorker
ans =
[]
>> parfor i=1:2;disp(getCurrentWorker);end
Worker
Host: IMP.OIMRDS
ComputerType: WIN64
ProcessId: 15784
Worker
Host: IMP.OIMRDS
ComputerType: WIN64
ProcessId: 17220

Related

Correct use Bash wait command with unknown processes number

Im writing a bash script that essentially fires off a python script that takes roughly 10 hours to complete, followed by an R script that checks the outputs of the python script for anything I need to be concerned about. Here is what I have:
ProdRun="python scripts/run_prod.py"
echo "Commencing Production Run"
$ProdRun #Runs python script
wait
DupCompare="R CMD BATCH --no-save ../dupCompareTD.R" #Runs R script
$DupCompare
Now my issues is that often the python script can generate a whole heap of different processes on our linux server depending on its input, with lots of different PIDs AND we have heaps of workers using the same server firing off scripts. As far as I can tell from reading, the 'wait' command must wait for all processes to finish or for a specific PID to finish, but when i cannot tell what or how many PIDs will be assigned/processes run, how exactly do I use it?
EDIT: Thank you to all that helped, here is what caused my dilemma for anyone google searching this. I broke up the ProdRun python script into its individual script that it was itself calling, but still had the issue, I think found that one of these scripts was also calling another smaller script that had a "&" at the end of it that was ignoring any commands to wait on it inside the python script itself. Simply removing this and inserting a line of "os.system()" allowed all the code to run sequentially.
It sounds like you are trying to implement a job scheduler with possibly some complex dependencies between different tasks. I recommend to use a job scheduler instead. It allows you to specify to run those jobs whilst also benefitting from features like monitoring, handling exceptional cases, errors, ...
Examples are: the open source rundeck https://github.com/rundeck/rundeck or the commercial one http://www.bmcsoftware.uk/it-solutions/control-m.html
Make your Python program wait on the children it spawns. That's the proper way to fix this scenario. Then you don't have to wait for Python after it finishes (sic).
(Also, don't put your commands in variables.)

Is there a (simple) way to make one program automatically close when another does?

I have a problem which I think might be solvable with a batch file, but I've only used batch files once or twice and don't know enough to try and solve this on my own. For context I'm running Windows 10 Home Edition, and have some programming experience, though it is primarily mathematical, i.e. R and MATLAB.
The problem is this: I have two programs, in this case Spotify and Toastify, which run together, with Toastify running in the background. I'll refer to them as S and T, respectively. If I run T, S runs as well, but if I close S, T remains running in the background. For reasons of convenience, I would rather that closing S also close T, so that when I want to use them again later I need only reopen T rather than checking if it's still running in the background, because T doesn't let you run multiple instances.
I'm wondering if there is an easy way to write a batch file (or something else if this isn't a good approach) that will open T (and so also S), and then 'listen' for S to close, at which point it closes T as well.
You need to use a Job Object. See Working example of CreateJobObject/SetInformationJobObject pinvoke in .net? and Kill child process when parent process is killed
Do not try 'monitoring for one process', that leaves zombies when the monitoring crashes.

Check status of a forked process?

I'm running a process that will take, optimistically, several hours, and in the worst case, probably a couple of days.
I've tried a couple of times to run it and it just never seems to complete (I should add, I didn't write the program, it's just a big dataset). I know my syntax for the command is correct as I use it all the time for smaller data and it works properly (I'll spare you the details as it is obscure for SO and I don't think that relevant to the question).
Consequently, I'd like to leave the program unattended running as a fork with &.
Now, I'm not totally sure whether the process is just grinding to a halt or is running but taking much longer than expected.
Is there any way to check the progress of the process other than ps and top + 1 (to check CPU use).
My only other thought was to get the process to output a logfile and periodically check to see if the logfile has grown in size/content.
As a sidebar, is it necessary to also use nohup with a forked command?
I would use screen for this purpose. see the man for more reference
Brief summary how to use:
screen -S some_session_name - starts a new screen session named session_name
Ctrl + a + d - detach session
screen -r some_session_name returns you to your session

Count number of executions of batch-script

This is my problem, I've got a batch-script that I can't modify (lets call it foo) and I would like to count how many times/day this script is executed - to keep track of that data.
Preferably, I would like to write the number of executions with date and exit-code to some kind of log file.
So my question is if this is possible and in that case - how? To create a batch-script/something that works in the background and writes every execution of foo to a log.
(I know this would be easy if I could modify foo but I can't. Also, everything is running on WinXP machines.)
You could write a wrapper script that does the logging and calls the existing script. Then use the wrapper in place of the original script
Consider writing a program that interrogates the Task Manager.
See http://www.netomatix.com/ProcDiagnostics.aspx
You could, for example, write a simple Console app which runs on a timer; every 5 seconds it checks that your foo application process exists. If it finds that it does, it assumes that find as the start time of the application; if it doesn't find it, it assumes the application has now closed and logs that information. It wouldn't be accurate to the second by any means, but would give you a rough approximation of when the thing is running and closing.
You might be able to configure Process Monitor
http://technet.microsoft.com/en-us/sysinternals/bb896645.aspx to capture the information you require

how to stop a running script in Matlab [duplicate]

This question already has an answer here:
How to abort a running program in MATLAB?
(1 answer)
Closed 7 years ago.
I write a long running script in Matlab, e.g.
tic;
d = rand(5000);
[a,b,c] = svd(d);
toc;
It seems running forever. Becasue I press F5 in the editor window. So I cannot press C-Break to stop in the Matlab console.
I just want to know how to stop the script. I am current use Task Manager to kill Matlab, which is really silly.
Thanks.
Matlab help says this-
For M-files that run a long time, or that call built-ins or MEX-files that run a long time, Ctrl+C does not always effectively stop execution. Typically, this happens on Microsoft Windows platforms rather than UNIX[1] platforms. If you experience this problem, you can help MATLAB break execution by including a drawnow, pause, or getframe function in your M-file, for example, within a large loop. Note that Ctrl+C might be less responsive if you started MATLAB with the -nodesktop option.
So I don't think any option exist. This happens with many matlab functions that are complex. Either we have to wait or don't use them!.
If ctrl+c doesn't respond right away because your script is too long/complex, hold it.
The break command doesn't run when matlab is executing some of its deeper scripts, and either it won't log a ctrl sequence in the buffer, or it clears the buffer just before or just after it completes those pieces of code. In either case, when matlab returns to execute more of your script, it will recognize that you are holding ctrl+c and terminate.
For longer running programs, I usually try to find a good place to provide a status update and I always accompany that with some measure of time using tic and toc. Depending on what I am doing, I might use run time, segment time, some kind of average, etc...
For really long running programs, I found this to be exceptionally useful
http://www.mathworks.com/matlabcentral/fileexchange/16649-send-text-message-to-cell-phone/content/send_text_message.m
but it looks like they have some newer functions for this too.
MATLAB doesn't respond to Ctrl-C while executing a mex implemented function such as svd. Also when MATLAB is allocating big chunk of memory it doesn't respond. A good practice is to always run your functions for small amount of data, and when all test passes run it for actual scale. When time is an issue, you would want to analyze how much time each segment of code runs as well as their rough time complexity.
Consider having multiple matlab sessions. Keep the main session window (the pretty one with all the colours, file manager, command history, workspace, editor etc.) for running stuff that you know will terminate.
Stuff that you are experimenting with, say you are messing with ode suite and you get lots of warnings: matrix singular, because you altered some parameter and didn't predict what would happen, run in a separate session:
dos('matlab -automation -r &')
You can kill that without having to restart the whole of Matlab.
One solution I adopted--for use with java code, but the concept is the same with mexFunctions, just messier--is to return a FutureValue and then loop while FutureValue.finished() or whatever returns true. The actual code executes in another thread/process. Wrapping a try,catch around that and a FutureValue.cancel() in the catch block works for me.
In the case of mex functions, you will need to return somesort of pointer (as an int) that points to a struct/object that has all the data you need (native thread handler, bool for complete etc). In the case of a built in mexFunction, your mexFunction will most likely need to call that mexFunction in the separate thread. Mex functions are just DLLs/shared objects after all.
PseudoCode
FV = mexLongProcessInAnotherThread();
try
while ~mexIsDone(FV);
java.lang.Thread.sleep(100); %pause has a memory leak
drawnow; %allow stdout/err from mex to display in command window
end
catch
mexCancel(FV);
end
Since you mentioned Task Manager, I'll guess you're using Windows. Assuming you're running your script within the editor, if you aren't opposed to quitting the editor at the same time as quitting the running program, the keyboard shortcut to end a process is:
Alt + F4
(By which I mean press the 'Alt' and 'F4' keys on your keyboard simultaneously.)
Alternatively, as mentioned in other answers,
Ctrl + C
should also work, but will not quit the editor.
if you are running your matlab on linux, you can terminate the matlab by command in linux consule.
first you should find the PID number of matlab by this code:
top
then you can use this code to kill matlab:
kill
example:
kill 58056
To add on:
you can insert a time check within a loop with intensive or possible deadlock, ie.
:
section_toc_conditionalBreakOff;
:
where within this section
if (toc > timeRequiredToBreakOff) % time conditional break off
return;
% other options may be:
% 1. display intermediate values with pause;
% 2. exit; % in some cases, extreme : kill/ quit matlab
end

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