[HADOOP-18129] Change URI[] in INodeLink to String[] to reduce memory footprint of ViewFileSystem

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.4.0, 2.10.2, 3.3.5
• Fix Version/s: 3.4.0, 2.10.2, 3.3.5
• Component/s: viewfs
• Labels: pull-request-available
• Target Version/s: 3.4.0, 2.10.2, 3.3.5
• Hadoop Flags: Reviewed
• Assignee: Abhishek Das
• Reporter: Abhishek Das
• Created: 17/Feb/22 18:37
• Updated: 11/Feb/24 23:34
• Resolved: 18/Mar/22 00:30

Description

Around 40k instances of INodeLink each of which is taking memory ranging from 1680bytes to 1160bytes. Multiplying 40k with 1160bytes will give us approximate 45mb.

With changing from URI to String in INodeLink the memory consumed by each of the INodeLink objects has reduced from ~1160 bytes to ~320 bytes. Overall size becomes (40k X 320) 12mb

Issue Links

• is related to: HDFS-15289 Allow viewfs mounts with HDFS/HCFS scheme and centralized mount table
• links to: GitHub Pull Request #3996
• links to: GitHub Pull Request #4083