[HDDS-372] There are three buffer copies in BlockOutputStream

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.4.1
• Component/s: Ozone Client
• Target Version/s: 0.5.0
• Sprint: Done
• Assignee: Shashikant Banerjee
• Reporter: Tsz-wo Sze
• Created: 23/Aug/18 22:06
• Updated: 05/Aug/19 14:45
• Resolved: 09/Apr/19 05:01

Description

Currently, there are three buffer copies in ChunkOutputStream

1. from byte[] to ByteBuffer, and
2. from ByteBuffer to ByteString.
3. from ByteString to ByteBuffer for checskum computation

We should eliminate the ByteBuffer in the middle.

For zero copy io, we should support WritableByteChannel instead of OutputStream. It won't be done in this JIRA.

Issue Links

• contains: HDDS-1227 Avoid extra buffer copy during checksum computation in write Path