With the move to APITimer, in many occasion a histogram will not update
itself, instead it will be updated by the APITimer.
This breaks the update values functionality so that a histogram that is
included in an APITimer will not try to update it self.
Signed-off-by: Amnon Heiman <amnon@scylladb.com>
The use of mean and variance as histogram parameter names makes more
sense.
This also make it safe to use an empty histogram that holds no samples.
Signed-off-by: Amnon Heiman <amnon@cloudius-systems.com>
This patch replace the Histogram data and statistic calculation from the
JMX proxy to the API.
This way the count, sum, min, max variance and square sum are calculated
always on the server.
When an update is perform, the API would return the statistic with a
sample of the last n elements as a sample.
This implementation insure that the counters are correct. The
implementation also allows to set the minimal update interval.
The implementation adds a mutable getter for each of the parameters so
they could be set to their new value.
Signed-off-by: Amnon Heiman <amnon@cloudius-systems.com>
Three of the Metric in the yammer library are based on data that is
pushed to them: Counter, Histogram and Meter.
This patch modify the specific functionality by inherit the original
Meter, keeping its functionality and API, and modify the way the data is
collected.
For Counter: A call to count will be implementing by calling the API to
retreive a value.
For Meter: A call to count will be implementing by calling the API to
retreive a value, similiar to count, but the timer aspect of the Meter
remains the same.
For histogram: Histogram uses an internal sample container. To mimic the
behaviour, a call to any of the historgram get functionality will update
the sample container first. A timestamp of the last update limits the
number of updates that will be done by the histogram.
Signed-off-by: Amnon Heiman <amnon@cloudius-systems.com>
