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Re: [HTCondor-users] condor_suspend/continue vs. condor_hold/release



On 5/27/2013 4:53 PM, 钱晓明 wrote:
Hi, What is the difference between condor_suspend/continue and
condor_hold/release for vanilla jobs?
I see this for condor_hold in manual: "A currently running job that is
placed in the hold state by condor_hold is sent a hard kill signal." So
I think that this job will be killed and in HOLD state. What
condor_suspend do to a running job?


condor_hold kills the process(es) currently associated with the job, 
frees the machine slot that was running the job to run another job.
condor_suspend does NOT kill the process(es) associated with the job, 
but instead tells the operating system to not schedule any CPU time for 
the job (in Unix-land, this means sending a SIGSTOP signal to the job). 
 The job is still keeps the machine slot occupied - it is still 
consuming RAM (or at least swap), kernel resources like file 
descriptors, and disk.  But it is not consuming any CPU cycles until a 
condor_continue.
Weak analogy to playing a DVD of a movie: Think of condor_suspend like 
free-framing the playback of a movie DVD, while condor_hold is like 
ejecting the DVD and putting it back on a shelf to watch another day.
regards
Todd