Linux Kernel Process Management - process

First, i admit all the things i will ask are about our homework but i assure you i am not asking without struggling at least two hours.
Description: We are supposed to add a field called max_cpu_percent to task_struct data type and manipulate process scheduling algorithm so that processes can not use an higher percentage of the cpu.
for example if i set max_cpu_percent field as 20 for the process firefox, firefox will not be able to use more than 20% of the cpu.
We wrote a system call to set max_cpu_percent field. Now we need to see if the system call works or not but we could not get the value of the max_cpu_percent field from a user-spaced program.
Can we do this? and how?
We tried proc/pid/ etc can we get the value using this util?
By the way, We may add additional questions here if we could not get rid of something else
Thanks All
Solution:
The reason was we did not modify the code block writing the output to the proc queries.
There are some methods in array.c file (fs/proc/array.c) we modified the function so that also print the newly added fields value. kernel is now compiling we'll see the result after about an hour =)
It Worked...

(If you simply extended getrlimit/setrlimit, then you'd be done by now…)
There's already a mechanism where similar parts of task_struct are exposed: /proc/$PID/stat (and /proc/$PID/$TID/stat). Look for functions proc_tgid_stat and proc_tid_stat. You can add new fields to the ends of these files.

Related

Getting the values of an /AIF/ERR variant

I did try using the RS_VARIANT_CONTENTS and RS_VARIANT_VALUES_TECH_DATA, it did show the values of the variant except the values of the name space, interface and interface version in which I also need to retrieve. I also searched the VARI* and TVARC tables but I didn't found it there.
I think it has something to do with the program name and screen number. Do you have any ideas or other way that I can retrieve all those values, whether using FM or select?
Thank you.
Some of the parameters in the transaction /AIF/ERR, the ones you are talking about, vary dynamically based on the value chosen in the Application screen field. They are handled by another AIF program, and they are not saved in the program variant, but in the table /AIF/T_ERR_VARS.
You may call the function module /AIF/ERR_VAR_LOAD to load the missing parameters.
Its usage is shown in the subroutine GET_VAR of the program /AIF/ERROR_HANDLING_TRANS (which is the program behind the transaction /AIF/ERR).

TFAgents: how to take into account invalid actions

I'm using TF-Agents library for reinforcement learning,
and I would like to take into account that, for a given state,
some actions are invalid.
How can this be implemented?
Should I define a "observation_and_action_constraint_splitter" function when
creating the DqnAgent?
If yes: do you know any tutorial on this?
Yes you need to define the function, pass it to the agent and also appropriately change the environment output so that the function can work with it. I am not aware on any tutorials on this, however you can look at this repo I have been working on.
Note that it is very messy and a lot of the files in there actually are not being used and the docstrings are terrible and often wrong (I forked this and didn't bother to sort everything out). However it is definetly working correctly. The parts that are relevant to your question are:
rl_env.py in the HanabiEnv.__init__ where the _observation_spec is defined as a dictionary of ArraySpecs (here). You can ignore game_obs, hand_obs and knowledge_obs which are used to run the environment verbosely, they are not fed to the agent.
rl_env.py in the HanabiEnv._reset at line 110 gives an idea of how the timestep observations are constructed and returned from the environment. legal_moves are passed through a np.logical_not since my specific environment marks legal_moves with 0 and illegal ones with -inf; whilst TF-Agents expects a 1/True for a legal move. My vector when cast to bool would therefore result in the exact opposite of what it should be for TF-agents.
These observations will then be fed to the observation_and_action_constraint_splitter in utility.py (here) where a tuple containing the observations and the action constraints is returned. Note that game_obs, hand_obs and knowledge_obs are implicitly thrown away (and not fed to the agent as previosuly mentioned.
Finally this observation_and_action_constraint_splitter is fed to the agent in utility.py in the create_agent function at line 198 for example.

Run-State values within shape script EA

Enterprise Architect 13.5.
I made MDG technology extending Object metatype. I have a shape script for my stereotype working well. I need to print several predefined run-state parameters for element. Is it possible to access to run-state params within Shape ?
As Geert already commented there is no direct way to get the runstate variables from an object. You might send a feature request to Sparx. But I'm pretty sure you can't hold your breath long enough to see it in time (if at all).
So if you really need the runstate in the script the only way is to use an add-in. It's actually not too difficult to create one and Geert has a nice intro how to create it in 10 minutes. In your shape script you can print a string restult returned from an operation like
print("#addin:myAddIn,pFunc1#")
where myAddIn is the name of the registered operation and pFunc1 is a parameter you pass to it. In order to control the script flow you can use
hasproperty('addin:myAddIn,pFunc2','1')
which evaluates the returned string to match or not match the string 1.
I once got that to work with no too much hassle. But until now I never had the real need to use it somewhere in production. Know that the addin is called from the interpreted script for each shaped element on the diagram and might (dramatically) affect rendering times.

Calling MM42, dirty assign of variables in SAPLCTMS for atnam and atwrts - Any experience?

In a custom program I call the retail material transaction (change, so MM42).
The user could change attribute values ( meaning ATWRT ) which are placed on the screen.
The debugger tells me, that there are a lot of variables, some seem to be the right ones, IF ONLY ONE atwrt of an atnam is changed. In case of multiple atwrt changes on more than one atnam, my dirty assign would only know the LAST ATNAM and it's new ATWRT.
This question adresses those developers, which might have already done this and may give me a hint, which one of the dozens of tables could track all the atnams and atwrts and also being possible to assign it in my calling program,after the MM42 returns.
IS there anybody in here, who may have done this, so I could save a bit of (maybe even lost) time ?

Extracting information from a file variable in d3 pick basic

I have a file variable in d3 pick basic and I am trying to figure out what file it corresponds to.
I tried the obvious thing which was to say:
print f *suppose the file variable's name is f in this case
but that didn't work, because:
SELECTION: 58[B34] in program "FILEPRINTER", Line 7: File variable used
where string expression expected.
I also tried things like:
list f *didn't compile
execute list dict f *same error
execute list f *same error
but those also did not work.
In case any one is wondering, the reason I am trying to do this in the first place is that there is a global variable that is passed up and down in the code base I am working with, but I can't find where the global variable gets its value from.
That file pointer variable is called a "file descriptor". You can't get any information from it.
You can use the file-of-files to log Write events, and after a Write is performed by the code, check to see what file was updated. The details for doing this would be a bit cumbersome. You really should rely on the Value-Add Reseller or contract with competent assistance for this.
If this is not a live end-user system, you can also modify an item getting written with some very unique text like "WHAT!FILE!IS!THIS?". Then you can do a Search-System command to search the entire account (or system) to find that text. See docs for proper use of that command.
This is probably the best option... Inject the following:
IF #USER = "CRISZ" THEN ; * substitute your user ID
READU FOO FROM F,"BLAH" ELSE
DEBUG
RELEASE F,"BLAH"
END
END
That code will stop only for one person - for everyone else it will flow as normal. When it does stop, use the LIST-LOCKS command to see which file has a read lock for item "BLAH". That's your file! Don't forget to remove and recompile the code. Note that recompiling code while users are actively using it results in aborts. It's best to do this kind of thing after hours or on a test system.
If you can't modify the code like that, diagnostics like this can be difficult. If the above suggestions don't help, I think this challenge might be beyond your personal level of experience yet and recommend you get some help.
If suggestion here Does help, please flag this as the answer. :)