Asynchronously Deleting HDFS Data

Scenario

The HDFS asynchronous deletion feature is used to delete large directories. Deleting blocks asynchronously with traffic control can effectively shorten the continuous lock period.

This function is available in MRS 3.5.0 or later only.

Procedure

1. Go to the All Configurations page of HDFS by referring to Modifying Cluster Service Configuration Parameters.
2. Enter the parameter name in the search box and modify the HDFS service-level parameter as you need.

   Table 1 Parameters for configuring HDFS asynchronous deletion

   Parameter	Description	Default Value
   dfs.namenode.block.deletion.async	Whether to enable asynchronous block deletion.	true
   dfs.namenode.block.deletion.lock.threshold.ms	Maximum duration for continuously lock a directory or file. After asynchronous block deletion is enabled, the specified maximum value is applied. Unit: millisecond	50
   dfs.namenode.block.deletion.lock.threshold.ms	Temporary unlock duration when the lock duration exceeds the maximum. Unit: millisecond	10

3. Save the configuration.
4. Click the Instances tab, select all instances whose configurations have expired, choose More > Restart Instance, and restart the instances as prompted.