问题描述
我们正在处理定期收到的消息.我们使用codahale dropwizard指标的计时器"来衡量处理它们所需的时间.
We are processing messages that comes in periodically. We use codahale dropwizard metrics' "Timer" for measuring the time it takes to process them.
我发现有人在此处遇到相同的问题:存储量呈指数递减的问题是，如果没有新数据输入，它将始终保持相同的数字.例如，假设您将计时器更新为5和7(那么就什么都不用了) ，那么无论您何时看到(即使在x小时后)，计时器仍将显示平均值为6，无论如何均不能代表最近5分钟.因此，仅当数据一直在到达时才有效."
I found someone had the same issue here:"problem with exponentially decaying reservoir is that if no new data comes in, it will keep on giving the same numbers all the times. For example, let say you update a timer with 5 and 7 (then don't put anything at all) , then no matter when you see (even after x hours), timer will still show the average to be 6 which is not representative of last 5 mins by any means.so, it works only if data is arriving all the time."
如深蓝色线所示:
但是没有解决的建议.他们说这将不会实现: https://github.com/dropwizard/metrics/Issues/399
But there's no suggestion to solve it. And they say it's not going to be implemented: https://github.com/dropwizard/metrics/issues/399
如何正确重置这些计时器，或者应该如何对其进行可视化处理，以免造成混淆?
How can I reset these timers properly or how should I visualize it so it's not confusing?
推荐答案
Note: It is too long for comment.
使用SlidingTimeWindowReservoir将涵盖大多数用例.但正如此评论中指出的那样，可能会出现问题，具体取决于事件数:它将所有测量结果保存在内存窗口中，这在发生大量事件时变得不可接受
Using the SlidingTimeWindowReservoir will cover most of the use-cases.But as pointed out in this comment there could be a problem depending on the number of events:it keeps all the measurements in the window in-memory which becomes unacceptable at large number of events
我们可以做得更好吗?让我们继续搜索.如果幸运的话，我们会找到此博客文章.它准确地描述了您的问题类型.有一个指向他们简单的肮脏解决方案的链接.另外建议使用 HdrHistogram .
Could we do better? Let's continue searching. If we are lucky we will find this blog post. It describes exactly your kind of problem. There is a link to their simple dirty solution. Also a suggestion for using HdrHistogram.
在指标邮件列表上，还有几条有关正是这个问题.对于示例并指向 Marshall Pierce/hdrhistogram-metrics-reservoir .什么是HdrHistogram?为什么要用它来测量延迟?请检查项目说明.
Also on the metrics mailing list there are several messages about exactly this problem.For example and point to Marshall Pierce/hdrhistogram-metrics-reservoir. What is HdrHistogram and why use it to measure latencies check the project description.
最后，在进一步挖掘之后，您还可以找到 vladimir-bukhtoyarov/metrics-core-hdr项目.它也在使用HdrHistogram.
And finally after some more digging you could find also vladimir-bukhtoyarov/metrics-core-hdr project. It's using HdrHistogram also.
因此，有两个类似的库使用相同的数据结构并声称可以解决您遇到的问题.
So there are two similar libraries that use the same data structure and claim to solve the problem case you have hit.
这篇关于如何重置Dropwizard指标的计时器?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！