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From "Edward Capriolo (JIRA)" <>
Subject [jira] [Commented] (CASSANDRA-12643) Estimated histograms tend to overflow
Date Sat, 12 Nov 2016 00:25:58 GMT


Edward Capriolo commented on CASSANDRA-12643:

I think the right fix should actually be on LibratoReporter to print which metric is overflowed
when getting an exception
That would be the right fix but that is not the easy fix. Unfortunately, the abstraction provided
by reporters only provide you a reportGauge(). You can not redefine that functionality without
changing the metric-reporting classes.

That is really the big problem the code looks like this: (and is not code defined in apache-cassandra)

for(Gauge g: gauges){
for(Counter c: counters){

Basically most reporters do NOT even try catch so throwing any exception generally just causes
the reporter to fail and result in only some things getting counter. Basically nothing anywhere
exceptions any metric to throw any exception or assertion.

I agree it would be idea to see name/ values. But its not easy. 

I think if we just show the values it would be basically easy to determine why the algorithm
overflows. The name is fairly meaningless. If the values are 0,0,0 we can feed that into a
unit test and reason about what it is supposed to do.

> Estimated histograms tend to overflow
> -------------------------------------
>                 Key: CASSANDRA-12643
>                 URL:
>             Project: Cassandra
>          Issue Type: Bug
>            Reporter: Edward Capriolo
>            Assignee: Edward Capriolo

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