[HDFS-1441] Infinite WAITING on dead s3n connection.

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Not A Problem
• Affects Version/s: 0.20.1

Environment

Debian 64 bit. Cloudera hadoop distro

• Assignee: Unassigned
• Reporter: Hajo Nils Krabbenhöft
• Created: 06/Oct/10 12:59
• Updated: 31/Jul/14 00:18
• Resolved: 31/Jul/14 00:18

Description

I am trying to read an image from a s3n URL as follows:

final FileSystem fileSystem;
fileSystem = FileSystem.get(new URI(filePath), config);
final FSDataInputStream fileData = fileSystem.open(new Path(filePath));
baseImage = ImageIO.read(fileData);
fileData.close();

When the ImageIO.read fails, i catch the exception and retry. It works flawlessly on the first four retries, but on the fifth retry, the fileSystem.open command block infinitely.
Here's the stack trace:

"Thread-83" prio=10 tid=0x00007f9740182000 nid=0x7cbc in Object.wait() [0x0000000040bbf000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)

• waiting on <0x00007f974a822438> (a org.apache.commons.httpclient.MultiThreadedHttpConnectionManager$ConnectionPool)
  at org.apache.commons.httpclient.MultiThreadedHttpConnectionManager.doGetConnection(MultiThreadedHttpConnectionManager.java:509)
• locked <0x00007f974a822438> (a org.apache.commons.httpclient.MultiThreadedHttpConnectionManager$ConnectionPool)
  at org.apache.commons.httpclient.MultiThreadedHttpConnectionManager.getConnectionWithTimeout(MultiThreadedHttpConnectionManager.java:394)
  at org.apache.commons.httpclient.HttpMethodDirector.executeMethod(HttpMethodDirector.java:152)
  at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:396)
  at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:324)
  at org.jets3t.service.impl.rest.httpclient.RestS3Service.performRequest(RestS3Service.java:357)
  at org.jets3t.service.impl.rest.httpclient.RestS3Service.performRestHead(RestS3Service.java:652)
  at org.jets3t.service.impl.rest.httpclient.RestS3Service.getObjectImpl(RestS3Service.java:1556)
  at org.jets3t.service.impl.rest.httpclient.RestS3Service.getObjectDetailsImpl(RestS3Service.java:1492)
  at org.jets3t.service.S3Service.getObjectDetails(S3Service.java:1793)
  at org.jets3t.service.S3Service.getObjectDetails(S3Service.java:1225)
  at org.apache.hadoop.fs.s3native.Jets3tNativeFileSystemStore.retrieveMetadata(Jets3tNativeFileSystemStore.java:111)
  at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
  at java.lang.reflect.Method.invoke(Method.java:597)
  at org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:82)
  at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:59)
  at org.apache.hadoop.fs.s3native.$Proxy1.retrieveMetadata(Unknown Source)
  at org.apache.hadoop.fs.s3native.NativeS3FileSystem.getFileStatus(NativeS3FileSystem.java:355)
  at org.apache.hadoop.fs.FileSystem.exists(FileSystem.java:690)
  at org.apache.hadoop.fs.s3native.NativeS3FileSystem.open(NativeS3FileSystem.java:476)
  at org.apache.hadoop.fs.FileSystem.open(FileSystem.java:398)
  at com.spratpix.mapreduce.MapUrl2ImageData.loadImageAndStoreTo(MapUrl2ImageData.java:226)

I suppose this is because S3 is throttling connections to the same file, but the s3n client cannot handle that correctly.