[BUG] ArithmeticException

[FMX]

What is the bug?

A clear and concise description of what the bug is.

How to reproduce the bug?

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Could you share logs or screenshots?

22/06/27 12:29:15,819 WARN [nioEventLoopGroup-6-2] DefaultChannelPipeline: An exceptionCaught() event was fired, and it reached at the tail of the pipeline. It usually means the last handler in the pipeline did not handle the exception.
java.lang.ArithmeticException: / by zero
at com.aliyun.emr.rss.service.deploy.master.Master.$anonfun$masterSource$9(Master.scala:97)
at com.aliyun.emr.rss.service.deploy.master.Master.$anonfun$masterSource$9$adapted(Master.scala:96)
at scala.collection.TraversableOnce.$anonfun$count$1(TraversableOnce.scala:119)
at scala.collection.TraversableOnce.$anonfun$count$1$adapted(TraversableOnce.scala:118)
at scala.collection.Iterator.foreach(Iterator.scala:941)
at scala.collection.Iterator.foreach$(Iterator.scala:941)
at scala.collection.AbstractIterator.foreach(Iterator.scala:1429)
at scala.collection.IterableLike.foreach(IterableLike.scala:74)
at scala.collection.IterableLike.foreach$(IterableLike.scala:73)
at scala.collection.AbstractIterable.foreach(Iterable.scala:56)
at scala.collection.TraversableOnce.count(TraversableOnce.scala:118)
at scala.collection.TraversableOnce.count$(TraversableOnce.scala:116)
at scala.collection.AbstractTraversable.count(Traversable.scala:108)
at com.aliyun.emr.rss.service.deploy.master.Master.$anonfun$masterSource$8(Master.scala:96)
at com.aliyun.emr.rss.service.deploy.master.Master.$anonfun$masterSource$8$adapted(Master.scala:96)
at com.aliyun.emr.rss.common.metrics.source.GaugeSupplier$$anon$2.getValue(AbstractSource.scala:326)
at com.aliyun.emr.rss.common.metrics.source.AbstractSource.recordGauge(AbstractSource.scala:225)
at com.aliyun.emr.rss.common.metrics.source.AbstractSource.$anonfun$getMetrics$2(AbstractSource.scala:284)
at com.aliyun.emr.rss.common.metrics.source.AbstractSource.$anonfun$getMetrics$2$adapted(AbstractSource.scala:284)
at scala.collection.immutable.List.foreach(List.scala:392)
at com.aliyun.emr.rss.common.metrics.source.AbstractSource.getMetrics(AbstractSource.scala:284)
at com.aliyun.emr.rss.common.metrics.sink.PrometheusServlet.$anonfun$getMetricsSnapshot$1(PrometheusServlet.scala:42)
at scala.collection.mutable.ResizableArray.foreach(ResizableArray.scala:62)
at scala.collection.mutable.ResizableArray.foreach$(ResizableArray.scala:55)
at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:49)
at com.aliyun.emr.rss.common.metrics.sink.PrometheusServlet.getMetricsSnapshot(PrometheusServlet.scala:42)
at com.aliyun.emr.rss.common.metrics.sink.PrometheusHttpRequestHandler.handleRequest(PrometheusServlet.scala:60)
at com.aliyun.emr.rss.service.deploy.master.http.HttpRequestHandler.channelRead0(HttpRequestHandler.scala:47)
at com.aliyun.emr.rss.service.deploy.master.http.HttpRequestHandler.channelRead0(HttpRequestHandler.scala:31)
at io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:99)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:103)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
at io.netty.channel.CombinedChannelDuplexHandler$DelegatingChannelHandlerContext.fireChannelRead(CombinedChannelDuplexHandler.java:436)
at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:327)
at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:299)
at io.netty.channel.CombinedChannelDuplexHandler.channelRead(CombinedChannelDuplexHandler.java:251)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1410)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:919)
at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:166)
at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:722)
at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:658)
at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:584)
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:496)
at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:995)
at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
at java.lang.Thread.run(Thread.java:748)

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