The Condor system [#LitzkowCAHOI##1#] is one of the most advanced load sharing systems to date. It operates in a workstation environment, aiming to maximise the utilisation of workstations with as little interference as possible between the jobs it schedules and the activities of the people who own the workstations. It identifies idle workstations and schedules background jobs on them. When the owner of a workstation resumes activity at a station, Condor checkpoints the remote job running on the node and transfers it to another machine. They claim that the overhead needed to support remote execution is very low. The Condor project has conducted work in three major areas:
  1. The gathering and analysis of workstation usage patterns.
  2. The exploration of algorithms for the management of idle workstation capacity. This resulted in the design of the Up-Down algorithm [#MutkaSRPCI##1#] which allows fair access to remote capacity for light users of the system in spite of large demands from heavy users.
  3. The development of remote execution facilities, known as Remote Unix [#LitzkowRU##1#].
In order to make the Condor system attractive to its potential users several issues requiring attention were identified: