EdColeman commented on issue #4498: URL: https://github.com/apache/accumulo/issues/4498#issuecomment-2101412344
The tension between a counter and a gauge is what the intended usage is. Your interpretation seems to be that the by_type should be a snapshot of an instant in time. That is not necessarily incorrect. Using a counter provides a different view. Because a counter is always increasing you can reason about things between measurements. It is not the instantaneous value but the absolute value that is reported. The absolute value allows using the delta and the rate of change of the value over time to be determined. The counter answers how many X's have ever occurred. For example, how many compactions have occurred over the last T? One way the counter is useful - say you look at an instantaneous snapshot and there are 0 compactions. No problem, that seems normal. However, if you looked over the last 24 hours and there were never any compactions you might need to look at things. The counter allows you to look at things like how many compactions happened over the last reporting period - has that increased? Counters also allow you to aggregate between reporting periods. With a snapshot you just need to hope that it hits at the measurement time. A counter also provides a way to trend things. For example you may want to trend bulk imports - Is there a surge at certain times? Does it vary by day? A counter can answer that, a gauge cannot. Using a combination of gauges (a snapshot of state) as well as counters to provide for trending and history may be appropriate. Think how it would be displayed on a dashboard. The gauges are the state right now. The counters could be graphs. showing the activity over the last few hours. So using a counter provides a view into activity over-time. Which is also not incorrect. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
