Non-Teaching Use of the System

The network of workstations in the DPO, The Department’s Central Computing System, is primarily intended to provide a modern teaching facility for over 1000 undergraduates. When not being used for teaching, the system provides a valuable computing resource for research. The Department wants the system to be as widely available as possible for research and private study as well as teaching but is concerned that adequate performance must be available for teaching during classes and therefore some restrictions on other use are necessary.

The need for and timing of the restricted periods is kept under regular review and users will be kept informed of any changes. Please note that un-timetabled teaching-related use of the system takes priority over un-timetabled research use, reflecting the primary role of the system as a teaching resource, but it is very rare for the load to be high enough outside restricted periods for this to a factor. We very much hope that users will voluntarily adhere to these restrictions so that the need for rigidly enforced automatic access controls can be avoided.

General Guidelines on Use

gate.eng.cam.ac.uk is not used for timetabled teaching but comprises low powered machines configured similarly to the computers in the DPO and intended for external access and “light work” only. Processes making excessive use of this system may be killed without warning.

If you need to do more compute intensive or long-running work please use ts-access (the collective name for a group of fast machines) outside teaching periods. iib-projects is the same kind of machine but is not used for timetabled teaching – it is intended for use by Part IIB students (who have priority at all times) and some research activities. All these systems run Linux.

Whilst the printers in the DPO may be used for non-teaching work, anyone wishing to send significant amounts to these printers should avoid timetabled teaching periods and if in doubt check with the DPO Manager first of all. Other Managed Print Service printers around the Department provide the same functionality.

Rules Governing Use During Peak Teaching Times

The Department has specified the following regulations for access to the Central Computing System during teaching hours for non-teaching use. These regulations are intended to give the maximum possible access consistent with acceptable performance for teaching. The system is based largely on trust and we hope that people will follow these rules as a matter of honesty. Those who persistently do not may deemed to be in breach of the Rules and may be prevented from using the system or have other sanctions taken against them.

1. No remote logins are allowed to timetabled clusters during teaching periods.
2. During busy periods all non-timetabled users should ask the demonstrator whether they can use a machine (rather than waiting for a demonstrator to have to tell them to log off!).
3. The operators will monitor the system at times during a laboratory or when requested by demonstrators.
4. Anyone who ignores these rules will receive two warnings, any further transgressions will result in disciplinary action being taken.

General Guidelines on Use During Peak Teaching Times

Workstation clusters reserved for teaching classes are clearly identified by notices at the end of each bench. All other users should vacate these machines in good time before the start of a class to allow incoming students to find a free workstation with minimum delay. This is particularly important during the Part I courses when up to a hundred undergraduates are attempting to login at the same time. Workstations in unreserved clusters are often available for non-teaching use but please check with a demonstrator.

Postgraduates and staff who use the system for research may be asked to restrict their use during peak teaching hours to activities which generate only a light load on the system as a whole. Such activities include:

• reading mail
• Web browsing
• editing files
• small scale compilation
• execution of small short running “number-crunching” programs

If the system becomes overloaded it will be necessary to reduce the load by terminating non-teaching activities, possibly without warning.

At all times, long running jobs should be run using the appropriate facilities.