[HADOOP-4137] NPE in GangliaContext.xdr_string (GangliaContext.java:195)

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 0.18.0, 0.18.1
• Component/s: metrics
• Assignee: Unassigned
• Reporter: Michael Bieniosek
• Created: 09/Sep/08 21:37
• Updated: 20/Nov/08 23:20
• Resolved: 17/Nov/08 16:56

Description

Exception in thread "Timer thread for monitoring dfs" java.lang.NullPointerException
at org.apache.hadoop.metrics.ganglia.GangliaContext.xdr_string(GangliaContext.java:195)
at org.apache.hadoop.metrics.ganglia.GangliaContext.emitMetric(GangliaContext.java:138)
at org.apache.hadoop.metrics.ganglia.GangliaContext.emitRecord(GangliaContext.java:123)
at org.apache.hadoop.metrics.spi.AbstractMetricsContext.emitRecords(AbstractMetricsContext.java:304)
at org.apache.hadoop.metrics.spi.AbstractMetricsContext.timerEvent(AbstractMetricsContext.java:290)
at org.apache.hadoop.metrics.spi.AbstractMetricsContext.access$000(AbstractMetricsContext.java:50)
at org.apache.hadoop.metrics.spi.AbstractMetricsContext$1.run(AbstractMetricsContext.java:249)
at java.util.TimerThread.mainLoop(Unknown Source)
at java.util.TimerThread.run(Unknown Source)

It looks like this caused the datanode to hang, though I accidentally killed the datanode before I could dump its stack.

Issue Links

• duplicates: HADOOP-3422 Ganglia counter metrics are all reported with the metric name "value", so the counter values can not be seen
• relates to: HADOOP-3422 Ganglia counter metrics are all reported with the metric name "value", so the counter values can not be seen