HDFS-11282. Document the missing metrics of DataNode Volume IO operations. Contributed by Yiqun Lin.

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Arpit Agarwal 2017-01-05 19:34:32 -08:00
parent 0b8a7c18dd
commit 4a659ff40f

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@ -323,6 +323,37 @@ Each metrics record contains tags such as SessionId and Hostname as additional i
| `RemoteBytesWritten` | Number of bytes written by remote clients | | `RemoteBytesWritten` | Number of bytes written by remote clients |
| `BPServiceActorInfo` | The information about a block pool service actor | | `BPServiceActorInfo` | The information about a block pool service actor |
FsVolume
--------
Per-volume metrics contain Datanode Volume IO related statistics. Per-volume metrics are off by default. They can be enbabled by setting `dfs.datanode.fileio.events.class` to **org.apache.hadoop.hdfs.server.datanode.ProfilingFileIoEvents**, but enabling per-volume metrics may have a performance impact. Each metrics record contains tags such as Hostname as additional information along with metrics.
| Name | Description |
|:---- |:---- |
| `TotalMetadataOperations` | Total number (monotonically increasing) of metadata operations. Metadata operations include stat, list, mkdir, delete, move, open and posix_fadvise. |
| `MetadataOperationRateNumOps` | The number of metadata operations within an interval time of metric |
| `MetadataOperationRateAvgTime` | Mean time of metadata operations in milliseconds |
| `MetadataOperationLatency`*num*`s(50|75|90|95|99)thPercentileLatency` | The 50/75/90/95/99th percentile of metadata operations latency in milliseconds. Percentile measurement is off by default, by watching no intervals. The intervals are specified by `dfs.metrics.percentiles.intervals`. |
| `TotalDataFileIos` | Total number (monotonically increasing) of data file io operations |
| `DataFileIoRateNumOps` | The number of data file io operations within an interval time of metric |
| `DataFileIoRateAvgTime` | Mean time of data file io operations in milliseconds |
| `DataFileIoLatency`*num*`s(50|75|90|95|99)thPercentileLatency` | The 50/75/90/95/99th percentile of data file io operations latency in milliseconds. Percentile measurement is off by default, by watching no intervals. The intervals are specified by `dfs.metrics.percentiles.intervals`. |
| `FlushIoRateNumOps` | The number of file flush io operations within an interval time of metric |
| `FlushIoRateAvgTime` | Mean time of file flush io operations in milliseconds |
| `FlushIoLatency`*num*`s(50|75|90|95|99)thPercentileLatency` | The 50/75/90/95/99th percentile of file flush io operations latency in milliseconds. Percentile measurement is off by default, by watching no intervals. The intervals are specified by `dfs.metrics.percentiles.intervals`. |
| `SyncIoRateNumOps` | The number of file sync io operations within an interval time of metric |
| `SyncIoRateAvgTime` | Mean time of file sync io operations in milliseconds |
| `SyncIoLatency`*num*`s(50|75|90|95|99)thPercentileLatency` | The 50/75/90/95/99th percentile of file sync io operations latency in milliseconds. Percentile measurement is off by default, by watching no intervals. The intervals are specified by `dfs.metrics.percentiles.intervals`. |
| `ReadIoRateNumOps` | The number of file read io operations within an interval time of metric |
| `ReadIoRateAvgTime` | Mean time of file read io operations in milliseconds |
| `ReadIoLatency`*num*`s(50|75|90|95|99)thPercentileLatency` | The 50/75/90/95/99th percentile of file read io operations latency in milliseconds. Percentile measurement is off by default, by watching no intervals. The intervals are specified by `dfs.metrics.percentiles.intervals`. |
| `WriteIoRateNumOps` | The number of file write io operations within an interval time of metric |
| `WriteIoRateAvgTime` | Mean time of file write io operations in milliseconds |
| `WriteIoLatency`*num*`s(50|75|90|95|99)thPercentileLatency` | The 50/75/90/95/99th percentile of file write io operations latency in milliseconds. Percentile measurement is off by default, by watching no intervals. The intervals are specified by `dfs.metrics.percentiles.intervals`. |
| `TotalFileIoErrors` | Total number (monotonically increasing) of file io error operations |
| `FileIoErrorRateNumOps` | The number of file io error operations within an interval time of metric |
| `FileIoErrorRateAvgTime` | It measures the mean time in milliseconds from the start of an operation to hitting a failure |
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