D-PHYS Computer Usage Policies

Many computers at the Department of Physics are available for more than one purpose and used by more than one person. The D-PHYS encourages their optimal use by all interested parties connected to the D-PHYS. Research and Education done by and for the D-PHYS gets preferrential treatment and all use has to fall within the regulations set forth by the BOT and Swiss law. In this document we collect some information about the code of conduct we expect users to follow. If you haven't used our resources in a while come back here and check for the latest conventions.

Numeric Computations on the Linux Workstations (Background Jobs)

Many workstations would have idle CPUs most of the time if used only for their main purpose. Please use this idle time for your research projects and follow these conventions:

  • Do not run such jobs at all on our terminal servers phd-ltsp1.ethz.ch or phd-ltsp2.ethz.ch as there are usually dozens of users logged in and try to do their daily work on those machines. Clogging up those machines causes many users not being able to work anymore, so no long running or heavily resource consuming computing jobs are allowed on these two machines. Please use plumpy.ethz.ch instead, e.g. via SSH with X forwarding.
  • check when they are used for regular work, e.g. the student pool in HPV F 7.1 is used for exercises and lectures. Please stop your programs during such times and use the night time and weekends. You can also run jobs on plumpy.
  • coordinate with other users who are also currently using the idle time. If you are starting to use the computers you are expected to contact the others who are currently active. As there are usually only a few users, this communication shall be one-on-one (by e-mail, phone, or other means). If possible we recommend that each participant uses a number of workstations exclusively for a time rather than sharing the CPU by concurrent processes. This will generally give better throughput.
  • run your jobs at nice level 18. This way the occasional interactive session is not severely affected and your job will still get most of the CPU time. You can also renice a/or mulitple jobs at a later time pidof can be useful.
  • make sure your job does not use more memory than is physically available as RAM. Also leave some RAM for the interactive jobs. A goal of half the available RAM or less is ideal. Paging to the hard disk is very slow and a waste of resources.
Private and/or Personal Web Servers

In general it is not allowed to run a personal web server on the D-PHYS workstations. If you want to publish some files via the Internet, you can use your D-PHYS account to set up your personal webpage. You will still need to follow the rules set by the BOT. If you need web pages for a project we recommend you use a proper web server. Feel free to contact the ISG of the D-PHYS at isg@phys.ethz.ch.