[HDFS-9494] Parallel optimization of DFSStripedOutputStream#flushAllInternals( )

• Type: Sub-task
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 3.0.0-alpha1
• Component/s: hdfs-client
• Hadoop Flags: Reviewed
• Assignee: Rui Gao
• Reporter: Rui Gao
• Created: 02/Dec/15 01:32
• Updated: 12/May/16 18:13
• Resolved: 01/Feb/16 21:03

Description

Currently, in DFSStripedOutputStream#flushAllInternals( ), we trigger and
wait for flushInternal( ) in sequence. So the runtime flow is like:

Streamer0#flushInternal( )
Streamer0#waitForAckedSeqno( )
Streamer1#flushInternal( )
Streamer1#waitForAckedSeqno( )
…
Streamer8#flushInternal( )
Streamer8#waitForAckedSeqno( )

It could be better to trigger all the streamers to flushInternal( ) and
wait for all of them to return from waitForAckedSeqno( ), and then flushAllInternals( ) returns.