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HDFS-10547. DiskBalancer: fix whitespace issue in doc files. Contributed by Anu Engineer.

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Anu Engineer 2016-06-20 09:48:34 -07:00 committed by Arpit Agarwal
parent 0774412e41
commit c6ed54808d
2 changed files with 16 additions and 11 deletions
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2
hadoop-hdfs-project/hadoop-hdfs/src/site/markdown/HDFSCommands.md
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@ -436,7 +436,7 @@ Runs a HDFS dfsadmin client.
Usage:
hdfs diskbalancer
[-plan <datanode> -uri <namenodeURI>]
[-plan <datanode> -fs <namenodeURI>]
[-execute <planfile>]
[-query <datanode>]
[-cancel <planfile>]

25
hadoop-hdfs-project/hadoop-hdfs/src/site/markdown/HDFSDiskbalancer.md
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@ -64,11 +64,11 @@ The following sections discusses what commands are supported by disk balancer
| COMMAND\_OPTION | Description |
|:---- |:---- |
| `-out`| Allows user to control the output location of the plan file.|
| `-bandwidth`| Since datanode is operational and might be running other jobs, diskbalancer limits the amount of data moved per second. This parameter allows user to set the maximum bandwidth to be used. This is not required to be set since diskBalancer will use the deafult bandwidth if this is not specified.|
| `-thresholdPercentage`| Since we operate against a snap-shot of datanode, themove operations have a tolerance percentage to declare success. If user specifies 10% and move operation is say 20GB in size, if we can move 18GB that operation is considered successful. This is to accomodate the changes in datanode in real time. This parameter is not needed and a default is used if not specified.|
| `-maxerror` | Max error allows users to specify how many block copy operations must fail before we abort a move step. Once again, this is not a needed parameter and a system-default is used if not specified.|
| `-v`| Verbose mode, specifying this parameter forces the plan command to print out a summary of the plan on stdout.|
| `-out`| Allows user to control the output location of the plan file.|
| `-bandwidth`| Since datanode is operational and might be running other jobs, diskbalancer limits the amount of data moved per second. This parameter allows user to set the maximum bandwidth to be used. This is not required to be set since diskBalancer will use the deafult bandwidth if this is not specified.|
| `-thresholdPercentage`| Since we operate against a snap-shot of datanode, themove operations have a tolerance percentage to declare success. If user specifies 10% and move operation is say 20GB in size, if we can move 18GB that operation is considered successful. This is to accomodate the changes in datanode in real time. This parameter is not needed and a default is used if not specified.|
| `-maxerror` | Max error allows users to specify how many block copy operations must fail before we abort a move step. Once again, this is not a needed parameter and a system-default is used if not specified.|
| `-v`| Verbose mode, specifying this parameter forces the plan command to print out a summary of the plan on stdout.|
The plan command writes two output files. They are `<nodename>.before.json` which
captures the state of the datanode before the diskbalancer is run, and `<nodename>.plan.json`.
@ -89,7 +89,7 @@ Query command gets the current status of the diskbalancer from a datanode.
| COMMAND\_OPTION | Description |
|:---- |:---- |
|`-v` | Verbose mode, Prints out status of individual moves|
|`-v` | Verbose mode, Prints out status of individual moves|
### Cancel
@ -103,6 +103,11 @@ or
Plan ID can be read from datanode using query command.
### Report
Report command provides detailed report about a node.
`hdfs diskbalancer -fs http://namenode.uri -report -node {DataNodeID | IP | Hostname}`
Settings
--------
@ -111,7 +116,7 @@ There is a set of diskbalancer settings that can be controlled via hdfs-site.xml
| Setting | Description |
|:---- |:---- |
|`dfs.disk.balancer.enabled`| This parameter controls if diskbalancer is enabled for a cluster. if this is not enabled, any execute command will be rejected by the datanode.The default value is false.|
|`dfs.disk.balancer.max.disk.throughputInMBperSec` | This controls the maximum disk bandwidth consumed by diskbalancer while copying data. If a value like 10MB is specified then diskbalancer on the average will only copy 10MB/S. The default value is 10MB/S.|
|`dfs.disk.balancer.max.disk.errors`| sets the value of maximum number of errors we can ignore for a specific move between two disks before it is abandoned. For example, if a plan has 3 pair of disks to copy between , and the first disk set encounters more than 5 errors, then we abandon the first copy and start the second copy in the plan. The default value of max errors is set to 5.|
|`dfs.disk.balancer.block.tolerance.percent`| The tolerance percent sepcifies when we have reached a good enough value for any copy step. For example, if you specify 10% then getting close to 10% of the target value is good enough.|
|`dfs.disk.balancer.enabled`| This parameter controls if diskbalancer is enabled for a cluster. if this is not enabled, any execute command will be rejected by the datanode.The default value is false.|
|`dfs.disk.balancer.max.disk.throughputInMBperSec` | This controls the maximum disk bandwidth consumed by diskbalancer while copying data. If a value like 10MB is specified then diskbalancer on the average will only copy 10MB/S. The default value is 10MB/S.|
|`dfs.disk.balancer.max.disk.errors`| sets the value of maximum number of errors we can ignore for a specific move between two disks before it is abandoned. For example, if a plan has 3 pair of disks to copy between , and the first disk set encounters more than 5 errors, then we abandon the first copy and start the second copy in the plan. The default value of max errors is set to 5.|
|`dfs.disk.balancer.block.tolerance.percent`| The tolerance percent sepcifies when we have reached a good enough value for any copy step. For example, if you specify 10% then getting close to 10% of the target value is good enough.|