Setting affinity for spawned processes

[giampaolo]

From maciej.l...@gmail.com on June 28, 2012 15:31:05

What steps will reproduce the problem?  
1. import psutil
2. p = psutil.Process(0)
3. p.set_cpu_affinity([0]) 

What is the expected output?  
Sets an affinity for process spawned via call to: osutil.execute(...) 

What do you see instead?  
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "c:\Python\Python27\lib\site-packages\psutil\__init__.py", line 346, in 
set_cpu_affinity
    return self._platform_impl.set_process_cpu_affinity(cpus)
  File "c:\Python\Python27\lib\site-packages\psutil\_psmswindows.py", line 145, in wrapper
    raise AccessDenied(self.pid, self._process_name)
psutil.error.AccessDenied: (pid=0, name='System Idle Process') 

What version of psutil are you using? What Python version?  
psutil 0.5
Python 2.7.2 (default, Jun 12 2011, 15:08:59) [MSC v.1500 32 bit (Intel)] on win32 

On what operating system? Is it 32bit or 64bit version?  
Win7 x64 SP1 

Please provide any additional information below.  
As described in Issue #238 this should be possible.

Original issue: http://code.google.com/p/psutil/issues/detail?id=291

[giampaolo]

From g.rodola on June 28, 2012 06:37:09

Not sure what problem you are referring to here.
Is PID 0 supposed to be an alias for "set an affinity for spawned process in advance"?
Is that stated somewhere?
I can't see anything like that in "man sched_setaffinity" on Ubuntu 12.04.

[giampaolo]

From maciej.l...@gmail.com on June 28, 2012 22:29:13

Yes, it is - unfortunately I cannot find a corresponding document at the moment.

I guess it should be sufficient to call:
psutil.Process(os.getpid()) and then start subprocess.

[giampaolo]

From g.rodola on June 29, 2012 04:45:44

That would seem to be more likely.
Also, even if PID 0 has the meaning you are suggesting, psutil is not 
misbehaving in raising AccessDenied: it just means you don't have the 
permission to perform that particular action (sched_setaffinity(3) call) in 
which case you might try to use the root user and see what happens.
Closing out as invalid for now. If you find any reference to PID 0 please reopen.

Status: Invalid
Labels: OpSys-Linux