[HADOOP-8423] MapFile.Reader.get() crashes jvm or throws EOFException on Snappy or LZO block-compressed data

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.20.2
• Fix Version/s: 1.2.0, 2.0.2-alpha
• Component/s: io

Environment

Linux 2.6.32.23-0.3-default #1 SMP 2010-10-07 14:57:45 +0200 x86_64 x86_64 x86_64 GNU/Linux

• Target Version/s: 1.2.0
• Hadoop Flags: Reviewed
• Assignee: Todd Lipcon
• Reporter: Jason B
• Created: 22/May/12 15:41
• Updated: 11/Oct/12 17:45
• Resolved: 16/Jul/12 22:35

Description

I am using Cloudera distribution cdh3u1.

When trying to check native codecs for better decompression
performance such as Snappy or LZO, I ran into issues with random
access using MapFile.Reader.get(key, value) method.
First call of MapFile.Reader.get() works but a second call fails.

Also I am getting different exceptions depending on number of entries
in a map file.
With LzoCodec and 10 record file, jvm gets aborted.

At the same time the DefaultCodec works fine for all cases, as well as
record compression for the native codecs.

I created a simple test program (attached) that creates map files
locally with sizes of 10 and 100 records for three codecs: Default,
Snappy, and LZO.
(The test requires corresponding native library available)

The summary of problems are given below:

Map Size: 100
Compression: RECORD
==================
DefaultCodec: OK
SnappyCodec: OK
LzoCodec: OK

Map Size: 10
Compression: RECORD
==================
DefaultCodec: OK
SnappyCodec: OK
LzoCodec: OK

Map Size: 100
Compression: BLOCK
================
DefaultCodec: OK

SnappyCodec: java.io.EOFException at
org.apache.hadoop.io.compress.BlockDecompressorStream.getCompressedData(BlockDecompressorStream.java:114)

LzoCodec: java.io.EOFException at
org.apache.hadoop.io.compress.BlockDecompressorStream.getCompressedData(BlockDecompressorStream.java:114)

Map Size: 10
Compression: BLOCK
==================
DefaultCodec: OK

SnappyCodec: java.lang.NoClassDefFoundError: Ljava/lang/InternalError
at org.apache.hadoop.io.compress.snappy.SnappyDecompressor.decompressBytesDirect(Native
Method)

LzoCodec:
#

1. A fatal error has been detected by the Java Runtime Environment:
   #
2. SIGSEGV (0xb) at pc=0x00002b068ffcbc00, pid=6385, tid=47304763508496
   #
3. JRE version: 6.0_21-b07
4. Java VM: Java HotSpot(TM) 64-Bit Server VM (17.0-b17 mixed mode linux-amd64 )
5. Problematic frame:
6. C [liblzo2.so.2+0x13c00] lzo1x_decompress+0x1a0
   #