comnetwork removed a comment on pull request #1970:
URL: https://github.com/apache/hbase/pull/1970#issuecomment-649947198
@Apache9 , I already added comments for `WriteBase.getSyncedLength` like
following:
/**
*NOTE: We add this method for {@link WALFileLengthProvider} used for
replication, considering the
* case if we use {@link AsyncFSWAL},we write to 3 DNs
concurrently,according to the visibility
* guarantee of HDFS, the data will be available immediately when
arriving at DN since all the DNs
* will be considered as the last one in pipeline. This means
replication may read uncommitted data
* and replicate it to the remote cluster and cause data inconsistency.
* The method {@link WriterBase#getLength} may return length which just
in hdfs client buffer and not
* successfully synced to HDFS, so we use this method to return the
length successfully synced to HDFS
* and replication thread could only read writing WAL file limited by
this length.
* see also HBASE-14004 and this document for more details:
*
https://docs.google.com/document/d/11AyWtGhItQs6vsLRIx32PwTxmBY3libXwGXI25obVEY/edit#
*/
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org
