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README.md

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+INTRO
+Light-weight, minimalistic, low-overhead lib for collecting and publishing performance statistics in production systems.
+Calls to the lib are usually injected via AOP.
+
+Overview:
+- code calls Statistics.recordMeasurement(String metricName, long duration [, unit]) 
+- the measurement is added to a list of values to process and the call returns
+- a background thread processes new measurement, updating aggregate values etc.
+- the collected values are made available via publishers such as JmxPublisher and PeriodicalLogPublisher
+
+USAGE
+
+Statistics.recordMeasurement("myBizMethod", 60);
+// => asynch. stored and updated count, avg, min, max, std.dev, ...
+// Computation strategy: rolling window x all values
+
+STATS
+
+- ignore lowest and highest N values (random extreems far behind normal values)
+- count avg, 10 min, 10 max, std.dev.
+- running avg/dev or based on all values
+
+ATTRS OF INTEREST
+
+Count	attribute	The number of times this event has occurred.
+ErrorCount	attribute	The number of times this event ended in error.
+AverageTime	attribute	The average execution time, in the selected unit.
+MaxTime	attribute	The maximum execution time, in the selected unit.
+MinTime	attribute	The minimum execution time, in the selected unit.
+StandardDeviation	attribute	The standard deviation from the mean, in the selected unit.
+LastInvocation	attribute	The most recent date and time at which this event occurred.
+Units	attribute	The unit of measure for max, min, average, and stddev. Valid values are seconds, milliseconds, and nanoseconds. Defaults to milliseconds if unspecified.
+reset	operation	Reset statistics for this type of event.
+