[
https://issues.apache.org/jira/browse/HDFS-5732?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Amir Langer updated HDFS-5732:
------------------------------
Attachment: 0002-Separation-of-BM-from-NN-Step-2-Separate-memory-spac.patch
Separation of memory space between BM and NN. This is an incremental patch on
top of the patch for the first sub task (HDFS-5731)
NN=NameNode
BM=BlockManager
DN=DataNode
This patch mainly separates the block instances between BM and NN.
This means that Inodes contain different BlockInfo instances from the
BlocksMap.
The replications information is only maintained by the instances in the
BlocksMap - and those no longer contain a reference to the Inode but the id
instead. (The new object is called BlockReplicationInfo).
Improved API between BM and NN to pass more ids instead of references between
the two (Although not complete, still work to invest there).
Also - Separation of memory space meant there are a few "upcalls" - calls where
the BM calls the NN.
Some of these are normal (when the call originated from the DN and changed the
state of the block).
But some should be eliminated as they create a circular call NN->BM->NN.
Currently not a problem (and was always there) - but will become problematic
when we try and separate BM to its own process.
The next sub-task should deal with those.
> Separate memory space between BM and NN
> ---------------------------------------
>
> Key: HDFS-5732
> URL: https://issues.apache.org/jira/browse/HDFS-5732
> Project: Hadoop HDFS
> Issue Type: Sub-task
> Components: namenode
> Reporter: Amir Langer
> Attachments:
> 0002-Separation-of-BM-from-NN-Step-2-Separate-memory-spac.patch
>
>
> Change created APIs to not rely on the same instance being shared in both BM
> and NN. Use immutable objects / keep state in sync.
> BM and NN will still exist in the same VM work on a new BM service as an
> independent process is deferred to later tasks.
> Also, a one to one relation between BM and NN is assumed.
> This task should maintain backward compatibility.
--
This message was sent by Atlassian JIRA
(v6.1.5#6160)
