Re: [HTCondor-users] ProportionalSetSize not populated in recent Htcondor versions

[Todd Tannenbaum <tannenba@xxxxxxxxxxx>]

On 3/31/2026 1:33 PM, Ram Ban wrote:

Hi all,

I have updated my some systems from htcondor version 10.0.8 to 25.0.7 few months back.

I have recently noticed that ProportionalSetSize is not being populated in JobClassAds, even when on executes USE_PSS=true is given. It was present in old htcondor version

Is this expected or I have to change some settings for it?

Thanks and Regards 

Raman

    Hi Raman,
    
    Are you launching the HTCondor Execution Point (EP, i.e. the
    condor_startd etc) on Linux as root (i.e. at bootup via systemd) ?
    
    If yes, my suspicion about what changed here:
    
    IIRC, in HTCSS 10.x default memory usage was tracked by the
    "condor_procd" daemon running on the EP.  This daemon would
    periodically poll each process belonging to the job and sum up RSS,
    PSS, etc.  In HTCSS 25.x, the EP will use Linux kernel control
    groups ("cgroups") to track memory utilization by default if it is
    launched with root access.  Linux cgroups do not support reporting
    PSS, thus in HTCSS 25.x you likely just see ResidentSetSize (RSS)
    and MemoryUsage (which defaults to be the same as RSS). 
    
    I strongly suggest you stick with the defaults in HTCSS 25.x, and go
    with "MemoryUsage" as the attribute for memory (RAM) usage info. 
    Having the kernel track this information via cgroups is more
    accurate and also better at detecting/stopping  jobs that use too
    much memory quickly before bad things happen.  However, if you
    really insist on having PSS information, I could share configuration
    to tell HTCSS to not use cgroups and instead return to using the
    condor_procd like happened in HTCSS v10.  But I do not recommend
    this.
    
    Hope this helps,
    Todd