will store the derivative of the line going from the last to the
current value of the data source. This can be useful for gauges, for
example, to measure the rate of people entering or leaving a
-room. Internally, derive works exaclty like COUNTER but without
+room. Internally, derive works exactly like COUNTER but without
overflow checks. So if your counter does not reset at 32 or 64 bit you
might want to use DERIVE and combine it with a MIN value of 0.
data source from other data sources in the same <RRD>. It is similar to defining
a B<CDEF> argument for the graph command. Please refer to that manual page
for a list and description of RPN operations supported. For
-COMPUTE data sources, the following RPN operations are not supported: PREV,
+COMPUTE data sources, the following RPN operations are not supported: COUNT, PREV,
TIME, and LTIME. In addition, in defining the RPN expression, the COMPUTE
data source may only refer to the names of data source listed previously
in the create command. This is similar to the restriction that B<CDEF>s must
=item Mail Messages
-Assume you have a methode to count the number of messages transported by
+Assume you have a method to count the number of messages transported by
your mailserver in a certain amount of time, this give you data like '5
messages in the last 65 seconds'. If you look at the count of 5 like and
B<ABSOLUTE> datatype you can simply update the rrd with the number 5 and the
temperatures supplied for 100 hours (1200 * 300 seconds = 100
hours). The second RRA stores the minimum temperature recorded over
every hour (12 * 300 seconds = 1 hour), for 100 days (2400 hours). The
-third and the fourth RRA's do the same with the for the maximum and
+third and the fourth RRA's do the same for the maximum and
average temperature, respectively.
=head1 EXAMPLE 2
projects / rrdtool.git / blobdiff