[HDFS-8029] NPE during disk usage calculation on snapshot directory, after a sub folder is deleted

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Assignee: Kanaka Kumar Avvaru
• Reporter: Kanaka Kumar Avvaru
• Created: 31/Mar/15 14:24
• Updated: 01/Apr/15 15:59
• Resolved: 01/Apr/15 15:59

Description

ContentSummary computation is causing NullPointerException on snapshot directory if some sub directory is deleted.
Following are the steps to reproduce the issue.

1. Create a root directory "/test"
2. Create sub dir named as /test/sub1
3. Create sub dir in sub1 as /test/sub1/sub2
4. Create a file at /test/sub1/file1
5. Create a file at /test/sub1/sub2/file1
6. Enable shotshot on sub1 (hadoop dfsadmin -allowSnapshot test/sub1)
7. Create snapshot1 on /test/sub1
8. Delete directory /test/sub1/sub2 (recursively)
9. Create snapshot2 on /test/sub1
10. Execute du command on /test (hadoop fs -du /test/)

Gives NullPointerException in CLI. NameNode logs the exception as
... java.lang.NullPointerException at org.apache.hadoop.hdfs.server.namenode.ContentSummaryComputationContext.getBlockStoragePolicySuite(ContentSummaryComputationContext.java:122) ...

Issue Links

• is related to: HDFS-7824 GetContentSummary API and its namenode implementation for Storage Type Quota/Usage
• relates to: HDFS-7811 Avoid recursive call getStoragePolicyID in INodeFile#computeQuotaUsage