[HDFS-8580] Erasure coding: Persist cellSize in BlockInfoStriped and StripedBlocksFeature

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: HDFS-7285
• Hadoop Flags: Reviewed
• Assignee: Walter Su
• Reporter: Walter Su
• Created: 11/Jun/15 11:43
• Updated: 30/Sep/15 19:37
• Resolved: 17/Jun/15 18:36

Description

Zhe Zhang, Kai Zheng and I had a offline discussion. Here is what we thought: Add a cellSize field in BlockInfoStriped as a workaround, and deal with memory usage in follow-on.(HDFS-8059)

discussion in HDFS-8494:
from Walter Su:

I think BlockInfoStriped needs to keep cellSize.

from vinayrpet:

I too was thinking the same when the FSImageLoader problem has came up. This will increase the memory usage by ~4bytes for each block though.

from jingzhao

Also, we should consider adding a chunk size field to StripedBlockProto and removing the cell size field from HdfsFileStatus. In this way we can access the chunk size information in the storage layer.

==
update:
from jingzhao

For fsimage part, since HDFS-8585 just removes StripedBlockProto, I guess what we can do here is to either 1) add the cellSize information into StripedBlocksFeature in fsimage.proto, or 2) bring StripedBlockProto back and put block info and cell size there.

Issue Links

• blocks: HDFS-8530 Restore ECZone info inside FSImageLoader