[lm-announce] Reorganizing files on Zeus

[Jonathan Buzzard]

I have been asked for clarification on what reorganizing files means.
Basically it means one of two things

First taking a directory and renaming it, so that "Current" becomes
"2008". If that directory has 500GB of data in it, it will have to be
copied across again, and this will take some considerable time. There
are a number of users would seem to engage in this type of activity on a
semi regular basis.

The second thing, would be to take a bunch of files and move them
somewhere else on Zeus as part of a tidying up exercise. Again they will
have to be copied again from the old system to the new system, and it is
easy to move several hundred GB of files about Zeus and have it take
just a couple of seconds. However it will take many hours to copy that
data onto the new system.

Please note that this has a major impact on the backup of the file
system at anytime, and is one of the many reasons that performance of
Zeus is poor. It is unfortunately not going to be fixed in the new
system either, so it is best to plan ahead on how you are going to
organize your files and avoid this sort of activity.

Another really bad idea this week would be to copy a large amount of new
data onto the system from a USB or Firewire drive onto the system. Note
if you do have a large amount of data to copy onto the system please
raise a ticket, as there are ways available to us administrators to put
large amounts of data on the system that has minimal impact on other
users.

However in general you should just be able to use Zeus as normal for the
rest of this week.


JAB.

-- 
Jonathan A. Buzzard                      Tel: +441382-386998
Storage Administrator, College of Life Sciences
University of Dundee, DD1 5EH