[HDFS-10226] Track and use BlockScheduled size for DatanodeDescriptor instead of count.

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Assignee: Brahma Reddy Battula
• Reporter: Brahma Reddy Battula
• Created: 29/Mar/16 04:26
• Updated: 29/Mar/16 06:19

Description

Tracking count will result in inaccurate estimation of remaining space in case of different block sized files being written.

This issue can happen when parallel write happen with different block size.

For Example:
Datanode Capacity is 10GB, available is 2GB
ClientA wants to write 2 blocks with block size 1GB
ClientB wants to write 2 blocks with block size 128MB

Here ClientB thinks scheduled size 128MB *2 = 256MB and write success where clientA write will fail.