I<noping only> B<-u> forces UTF-8 output, B<-U> disables UTF-8 output. If
neither is given, the codeset is automatically determined from the locale.
-=item B<-g> B<none>|B<prettyping>|B<boxplot>
+=item B<-g> B<none>|B<prettyping>|B<boxplot>|B<histogram>
I<noping only> Selects the graph to display.
=item B<none>
-Do not shot a graph.
+Do not show a graph.
=item B<prettyping>
-Show a graph with time on the x-axis in a round-robin fashion, i.e. continue on
-the left if the right edge is reached. The y-axis shows the round-trip time.
-This is the default.
+Show a graph with time on the x-axis, the y-axis shows the round-trip time.
+This is the default graph.
+
+If your terminal supports unicode and colors, they are used to improve
+the precision of the data shown: a green box is drawn for round-trip times up
+to one third of the configured timeout, the height representing the RTT. Longer
+RTTs will start to fill the box yellow (with a green background) and then red
+(with a yellow background). Lost packages are drawn as a bold red explamation
+mark.
=item B<boxplot>
-Shows a box plot where the x-axis, i.e. the width of the window, is the
+Show a I<box plot> where the x-axis, i.e. the width of the window, is the
round-trip time. The entire width of the window it the ping interval, set with
the B<-i> option.
median. The whiskers are sized to contain 95% of the replies -- 2.5% below the
whiskers and 2.5% above.
+ |----------[#####|##########]--------------------------------------------|
+ ^ ^ ^ ^ ^
+ 2.75% 25% 50% 75% 97.5%
+
+=item B<histogram>
+
+Show a I<histrogram> of the round-trip times. The width of the window is taken
+as round-trip time from 0ms on the left to the I<interval> (the B<-i> option,
+default 1000ms) on the right.
+
+The height of the graph is scaled so that the most-used buckets vertically fills
+the line. The buckets are colored green up to and including the 80th
+percentile, yellow up to and including the 95th percentile and red for the
+remainder.
+
=back
=item B<-P> I<percent>
between zero and 100, exclusively in both cases. In general, defaults to B<95>.
If B<-c> is given and a number less than 20, this would be the same as the
maximum. In this case the default is chosen so that it excludes the maximum,
-e.g. if B<-cE<nbsp>5> is given, the default is I<80>.
-
-The calculated percentile has roughly millisecond precision. If precision is of
-importance, read on for a more detailed explanation. In order to calculate the
-percentile without keeping all replies in memory, I<oping> divides the
-I<interval> (the B<-i> option) in 1000 "buckets". Each bucket counts the number
-of packets received in the represented time. That means that the precision
-decreases if the interval is increased, because each bucket represents a larger
-(fraction of the) response time. The code looks for the first bucket
-representing at least I<percent> responses and returns the upper-bound latency
-represented by that bucket. Since the represented percentage may be larger than
-the configured percentile, this algorithm I<overestimes> the actual percentile
-by at most 1000th of I<interval>.
+e.g. if B<-cE<nbsp>5> is given, the default is I<80>. The calculated percentile
+is based on the last 900 packets (15 minutes with the default interval).
=item B<-Z> I<percent>
the "expected" range, yellow marks moderately unusual times and times that
differ a lot from the expected value are printed in red.
-The information used to categorize round-trip times is the I<average>
-round-trip time and the I<standard deviation>. RTTs that differ from the
-average by less than the standard deviation are considered to be "normal" and
-are printed in green. Times that differ from the average more than the standard
-deviation but less than twice the standard deviation are considered "moderately
-unusual" and are printed in yellow. Times differing more than twice the
-standard deviation from the average are considered to be "unusual" and are
+The information used to categorize round-trip times is the I<percentile>. RTTs
+in the 80th percentile are considered to be "normal" and are printed in green.
+RTTs within the 95th percentile are considered "moderately unusual" and are
+printed in yellow. RTTs above that are considered to be "unusual" and are
printed in red.
=head1 SEE ALSO
=head1 AUTHOR
liboping is written by Florian "octo" Forster E<lt>ff at octo.itE<gt>.
-Its homepage can be found at L<http://verplant.org/liboping/>.
+Its homepage can be found at L<http://noping.cc/>.
Copyright (c) 2005-2011 by Florian "octo" Forster.
projects / liboping.git / blobdiff