Tenex load averages for July 1973 (RFC0546)
Original Publication Date: 1973-Aug-10
Included in the Prior Art Database: 2001-Nov-29
Internet Society Requests For Comment (RFCs)
This RFC presents utilization data for the BBN and ISI TENEX systems which may be of interest to the network community.
Network Working Group B. Thomas
Request for Comments: 546 BBN-TENEX
NIC: 17792 10 August 1973
TENEX Load Averages for July 1973
This RFC presents utilization data for the BBN and ISI TENEX systems
which may be of interest to the network community.
The graph on page 4 summarizes the load at the BBN-TENEX and USC-ISI
Hosts during the work week for the month of July 1973. The weekday
hourly load average  for each site is plotted versus the time of
day; the time of day is Eastern Daylight Time.
Interpreting data such as this is tricky business. However, it is
difficult to resist making the following observations:
1. The shapes of the BBN and ISI curves are approximately the same;
furthermore, there is no skew between the curves. This suggests
that the user populations for the two systems have similar working
habits and are acclimated to the same time zone.
2. The significant features of both curves appear to be strongly
correlated with "normal events" in the day of a user living on
East Coast time,suggesting that the load at both sites is
influenced most strongly by such users:
a. the load begins to increase between 7-8 a.m. EDT as users begin
their daily computing;
b. it dips between 10-11 a.m. EDT (smoothed to a smaller rate of
increase in the ISI curve) as users take their coffee break;
c. the load peaks sharply between 1-2 p.m. EDT as users return
from lunch to resume their computing;
d. it decreases as the afternoon continues and as users go home
e. it reaches a local minimum between 6-7 p.m. EDT (minimum not
present in ISI curve) when most people eat dinner;
f. it increases to an evening peak between 9-10 p.m. EDT as some
users come back from dinner and after dinner activities to
resume their computing.
Thomas [Page 1]
RFC 546 TENEX Load Averages for July 1973 10 August 1973
3. The curve for ISI is smoother than the one for BBN: the "coffee
break" dip appears only as a decrease in slope; the dinner break
and evening peak are completely smoothed out. This smoothing is
probably due to the influence of the West Coast users of the ISI
4. During July the BBN system was more heavily loaded than the ISI
system. Since the data collected did not include the number of...