[
https://issues.apache.org/jira/browse/HDFS-17049?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17733719#comment-17733719
]
ASF GitHub Bot commented on HDFS-17049:
---------------------------------------
Hexiaoqiao commented on PR #5743:
URL: https://github.com/apache/hadoop/pull/5743#issuecomment-1595672568
Back to this PR. Considering that blockId/blockGroupId generator is
protected by global lock, I think we do not need more `synchronized` protection
which has some time cost. However we should add some more explicit annotation
to note that `SequentialBlockGroupIdGenerator` is not thread-safe class.
> EC: Fix duplicate block group IDs generated by SequentialBlockGroupIdGenerator
> ------------------------------------------------------------------------------
>
> Key: HDFS-17049
> URL: https://issues.apache.org/jira/browse/HDFS-17049
> Project: Hadoop HDFS
> Issue Type: Bug
> Reporter: Shuyan Zhang
> Assignee: Shuyan Zhang
> Priority: Major
> Labels: pull-request-available
>
> When I used multiple clients to write EC files concurrently, I found that
> NameNode generated the same block group ID for different files:
> ```
> 2023-06-13 20:09:59,514 INFO org.apache.hadoop.hdfs.StateChange: BLOCK*
> allocate blk_-9223372036854697568_14389 for /ec-test/10/4068034329705654124
> 2023-06-13 20:09:59,514 INFO org.apache.hadoop.hdfs.StateChange: BLOCK*
> allocate blk_-9223372036854697568_14390 for /ec-test/19/7042966144171770731
> ```
> After diving into `SequentialBlockGroupIdGenerator`, I found that the current
> implementation of `nextValue` is not thread-safe.
> This problem must be fixed.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
