myschedd
In CERN's HTCondor batch system, there are multiple schedds, but users are assigned to a particular schedd. This is to make things simple, so that logging into, for instance, any LXPLUS machine, HTCondor commands can be run and your jobs can be queried without any knowledge of how the infrastructure is organized.
However, there are occasionally problems with schedds. For instance schedds can get busy! Since the usage is as hard to predict as the users that use them, how busy schedds can get is uneven. Therefore it might be useful to occasionally change schedd. Previously this required setting arcane environment variables. Now the tool myschedd allows this.
Showing the current configuration
$ myschedd show
User 'bejones' in pool 'share'
Current schedd: bigbird18.cern.ch
Other schedds used recently: bigbird08.cern.ch
Note the output shows not only the schedd you are currently assigned to, but also ones you've used previously. If you have jobs running on those other schedds, you can query them like so:
$ condor_q -name bigbird08.cern.ch
Switching to a new schedd
$ myschedd bump
Selected best schedd 'bigbird19.cern.ch' for user 'bejones' in pool 'share'
"Bump" will choose the least loaded schedd to use. We can see that our schedds list gets updated:
$ myschedd show
User 'bejones' in pool 'share'
Current schedd: bigbird19.cern.ch
Other schedds used recently: bigbird08.cern.ch, bigbird18.cern.ch
Setting a schedd explicitly
You normally won't want to do this, as the schedd is chosen specifically to be lightly used. However there may be circumstances you want to be explicit. First of all, it's worth remembering how to query the schedds that can be used:
$ condor_status -schedd
Name Machine RunningJobs IdleJobs HeldJobs
bigbird08.cern.ch bigbird08.cern.ch 5698 5670 251
bigbird09.cern.ch bigbird09.cern.ch 4009 1237 2803
bigbird10.cern.ch bigbird10.cern.ch 4850 50 5
bigbird11.cern.ch bigbird11.cern.ch 4089 846 1
bigbird12.cern.ch bigbird12.cern.ch 7498 22593 1
bigbird13.cern.ch bigbird13.cern.ch 7688 643 6314
bigbird14.cern.ch bigbird14.cern.ch 1237 23 489
bigbird15.cern.ch bigbird15.cern.ch 5466 3517 0
bigbird16.cern.ch bigbird16.cern.ch 7913 24603 521
bigbird17.cern.ch bigbird17.cern.ch 808 9844 0
bigbird18.cern.ch bigbird18.cern.ch 1200 72 0
bigbird19.cern.ch bigbird19.cern.ch 22 1 1
bigbird98.cern.ch bigbird98.cern.ch 0 0 65
bigbird99.cern.ch bigbird99.cern.ch 0 0 0
ce-test.cern.ch ce-test.cern.ch 0 0 0
ce503.cern.ch ce503.cern.ch 4417 305 4
ce504.cern.ch ce504.cern.ch 4875 284 1
ce505.cern.ch ce505.cern.ch 4471 277 2
ce506.cern.ch ce506.cern.ch 4655 159 0
ce507.cern.ch ce507.cern.ch 4003 239 0
ce508.cern.ch ce508.cern.ch 3726 406 1
ce509.cern.ch ce509.cern.ch 3635 361 3
ce510.cern.ch ce510.cern.ch 4411 334 1
ce511.cern.ch ce511.cern.ch 4262 321 3
ce512.cern.ch ce512.cern.ch 4126 387 2
ce513.cern.ch ce513.cern.ch 4186 345 0
ce514.cern.ch ce514.cern.ch 4232 187 0
ce515.cern.ch ce515.cern.ch 3195 212 0
ce516.cern.ch ce516.cern.ch 2959 95 0
cehpc.cern.ch cehpc.cern.ch 36 13 0
condorce01.cern.ch condorce01.cern.ch 4028 149 1
TotalRunningJobs TotalIdleJobs TotalHeldJobs
Total 111695 73173 10469
It should be stressed that you cannot select the "CE" machines as user schedds. The tool won't allow it in any case:
$ myschedd set ce503.cern.ch
Error: HTTP code: 404: Requested schedd (ce503.cern.ch) is not known
Setting it to something sensible will work:
$ myschedd set bigbird08.cern.ch
$ myschedd show
User 'bejones' in pool 'share'
Current schedd: bigbird08.cern.ch
Other schedds used recently: bigbird18.cern.ch, bigbird19.cern.ch