Re: [HTCondor-users] Best strategy for matchmaking based on schedd hostname

[jcaballero.hep@xxxxxxxxx]

El miÃ., 8 abr. 2020 a las 18:26, Todd Tannenbaum
(<tannenba@xxxxxxxxxxx>) escribiÃ:
>
> On 4/8/2020 11:33 AM, jcaballero.hep@xxxxxxxxx wrote:
> > Hello,
> >
> >
> > I need to add a constraint in my startd configuration to accept jobs
> > only from one of the several schedd's serving the pool.
> > IIRC, the schedd name is embedded in the GlobalJobId, right?
> > What would be the recommended strategy to extract the schedd name from
> > it and add it to the expression? Something like this?
> >
> >        split( GlobalJobId , "#" )[0] =?= my_schedd_hostname
> >
> >
> > Any suggestion is more than welcome.
> > Thanks a lot in advance.
> > Cheers,
> > Jose
>
> Hi Jose,
>
> I strongly advise that you do not reference GlobalJobId in your startd's START expression.  While it would work, it will
> result in the central manager doing a lot of extra work resulting in slower matchmaking when many jobs are queued.  The
> reason is because GlobalJobId has a unique value for every single job, and referencing a unique value in the START
> expression means that HTCondor can no longer automatically group jobs together when doing matchmaking... it will need to
> consider every single job individually.
>
> Instead, I recommend perhaps looking at the job's "User" attribute which is owner@xxxxxxxxxxxxx maybe this works for
> you?  Then you could have in the config on your execute machine something like:
>     START = splitUserName(User)[1] == "whatever"
>
> Another idea is to simply make a custom attribute in all the jobs coming from the schedd's you care about.  On your
> submit machine(s) you could put in condor_config something like the following to create a custom attribute ScheddHostName:
>
>    ScheddHostName = "$(FULL_HOSTNAME)"
>    SUBMIT_ATTRS = $(SUBMIT_ATTRS) ScheddHostName
>
> and then reference this custom attribute in your START expression on your execute nodes like so:
>
>    START = ScheddHostName == "whatever.gov"
>
> Hope the above helps,
> Todd

Thanks a lot, Todd.
For quick solution, I will try parsing the User.
Adding the schedd as a claasad is definitely the best solution for the
long term.

Cheers,
Jose