User`s guide

Graphs and Tables
Working with Graphs
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You can also control how much data is shown in the graph window with
the graph pop-up menu displayed by mouse button 3. Refer to figure 112
on page 529 for details.
For Live Statistics graphs and the Token Ring Source Routing graph, you
can control how often new points are added to the graph. The SNMP
Polling text field lets you change the rate at which points are added to
the graph. (This item is not shown in the Time Intervals… window for
graphs from the Historical Statistics and Internetwork Response
Manager applications.)
The Resolution option pop-up menu lets you control the resolution of
the data in the graph. Choose Resolution by data to display the data as
it was collected. Choose Resolution user defined and indicate a time
interval to use a different display resolution.
By default, the resolution of the displayed data is determined by the col-
lection interval at which the data was obtained. This is the most accurate
level of detail at which the data can be displayed. The default resolution
for the hourly Historical Statistics study is 5 seconds; for the daily study,
30 seconds; and for the monthly study, 1800 seconds or 30 minutes.
Increasing the resolution above the default (for example, to eight hours)
causes multiple data points to be averaged together, or normalized; that
is, the lines in the graph are “evened out,” and long-term trends become
apparent, even in rapidly fluctuating data. Less “noise” is displayed, and
spikes are filtered out.
Decreasing the resolution below the default (for example, to one second)
results in a “step” graph, which may give you misleading information. If
you see a step graph, the resolution is probably set too low.