[
https://issues.apache.org/jira/browse/HADOOP-15928?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Pranay Singh updated HADOOP-15928:
----------------------------------
Description:
Problem:
------------
There is excessive error logging when a file is opened by libhdfs
(DFSClient/HDFS) in S3 environment, this issue is caused because buffered read
is not supported in S3 environment, HADOOP-14603 "S3A input stream to support
ByteBufferReadable"
The following message is printed repeatedly in the error log/ to STDERR:
--------------------------------------------------------------------------------------------------
UnsupportedOperationException: Byte-buffer read unsupported by input
streamjava.lang.UnsupportedOperationException: Byte-buffer read unsupported by
input stream
at
org.apache.hadoop.fs.FSDataInputStream.read(FSDataInputStream.java:150)
Root cause
----------------
After investigating the issue, it appears that the above exception is printed
because
when a file is opened via hdfsOpenFileImpl() calls readDirect() which is
hitting this
exception.
Fix:
----
Since the hdfs client is not initiating the byte buffered read but is happening
in a implicit manner, we should not be generating the error log during open of
a file.
was:
Problem:
------------
There is excessive error logging when a file is opened by libhdfs
(DFSClient/HDFS) in S3 environment, this issue is caused because buffered read
is not supported in S3 environment, HADOOP-14603 "S3A input stream to support
ByteBufferReadable"
Excessive error logging results in defect IMPALA-5256: "ERROR log files can get
very large". This causes the error log files to be huge.
The following message is printed repeatedly in the error log:
UnsupportedOperationException: Byte-buffer read unsupported by input
streamjava.lang.UnsupportedOperationException: Byte-buffer read unsupported by
input stream
at
org.apache.hadoop.fs.FSDataInputStream.read(FSDataInputStream.java:150)
Root cause
----------------
After investigating the issue, it appears that the above exception is printed
because
when a file is opened via hdfsOpenFileImpl() calls readDirect() which is
hitting this
exception.
Fix:
----
Since the hdfs client is not initiating the byte buffered read but is happening
in a implicit manner, we should not be generating the error log during open of
a file.
> Excessive error logging when using HDFS in S3 environment
> ---------------------------------------------------------
>
> Key: HADOOP-15928
> URL: https://issues.apache.org/jira/browse/HADOOP-15928
> Project: Hadoop Common
> Issue Type: Improvement
> Reporter: Pranay Singh
> Assignee: Pranay Singh
> Priority: Major
> Attachments: HADOOP-15928.001.patch
>
>
> Problem:
> ------------
> There is excessive error logging when a file is opened by libhdfs
> (DFSClient/HDFS) in S3 environment, this issue is caused because buffered
> read is not supported in S3 environment, HADOOP-14603 "S3A input stream to
> support ByteBufferReadable"
> The following message is printed repeatedly in the error log/ to STDERR:
> --------------------------------------------------------------------------------------------------
> UnsupportedOperationException: Byte-buffer read unsupported by input
> streamjava.lang.UnsupportedOperationException: Byte-buffer read unsupported
> by input stream
> at
> org.apache.hadoop.fs.FSDataInputStream.read(FSDataInputStream.java:150)
> Root cause
> ----------------
> After investigating the issue, it appears that the above exception is printed
> because
> when a file is opened via hdfsOpenFileImpl() calls readDirect() which is
> hitting this
> exception.
> Fix:
> ----
> Since the hdfs client is not initiating the byte buffered read but is
> happening in a implicit manner, we should not be generating the error log
> during open of a file.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: common-issues-unsubscr...@hadoop.apache.org
For additional commands, e-mail: common-issues-h...@hadoop.apache.org
