|By Percentage:||Session 1||Session 2|
|By Numbers:||Session 1||Session 2|
Each Summary graph compares a session over all available years. For weekday, weekends and alldays: there are graphs comparing an average day of each week over the number of years; graphs comparing the progressive load during the session; and graphs showing the number of hours in each when when the labs were saturated (more than 80% utilised).
There are a number of anomolous artifacts in these graphs, the reasons for which belong in various historical events. For example, in some years the class bookings for labs were exclusive bookings. A result of this was that the lab might be less than half full, but because it was all reserved for the lab nobody else could log in and the lab should have been considered fully utilised. These plots (based on login records in system logs) can only indicate that the lab was less than half full at the time.
There are separate graphs for comparing the number of computers in use,
and the percentage of computers in use.
They are drawn directly from login records in system logs, and show (after a little fiddling), how many computers were in use in each lab for any time of the day.
To reduce the noise of logins/logouts on the hour and half-hour, samples have been taken at the quarter-past and quarter-to times (or the next available sample after that).
Organisationally, for presentation here, there is a page for each week of every session. Within these weekly pages, there are plots of all labs for each day, and plots of each lab for all days of the week.
Warning: The numbers for the last day or so may not be complete. The way the login information is collected usually results in the data from a few computers not being reported for a day or two.
Warning: Login information is not collected for many of the Special Labs. Thus the plots for these labs will typically indicate (erroneously) that they are unused.
Warning: The data for 1996 session 2 is very incomplete, to the point of being meaningless.