警告snappy.LoadSnappy:未加载Snappy本机库

Question

无论我做什么,我都无法摆脱这个错误.我知道snappy是一个快速的,因此比其他选项更适合压缩/解压缩库.我想使用这个库进行处理.据我所知,Google在内部使用了BigTables,MapReduce(基本上用于所有杀手级应用程序).我自己研究过.人们建议不要使用它,或者选择java-snappy,但我想坚持使用hadoop snappy.我的设置中有相应的库.(我的意思是在lib下)

有人可以修复此错误吗？无论出现此错误,我都看到作业已成功完成.

****hdfs://localhost:54310/user/hduser/gutenberg
12/06/01 18:18:54 INFO input.FileInputFormat: Total input paths to process : 3
12/06/01 18:18:54 INFO util.NativeCodeLoader: Loaded the native-hadoop library
12/06/01 18:18:54 WARN snappy.LoadSnappy: Snappy native library not loaded
12/06/01 18:18:54 INFO mapred.JobClient: Running job: job_201206011229_0008
12/06/01 18:18:55 INFO mapred.JobClient:  map 0% reduce 0%
12/06/01 18:19:08 INFO mapred.JobClient:  map 66% reduce 0%
12/06/01 18:19:14 INFO mapred.JobClient:  map 100% reduce 0%
12/06/01 18:19:17 INFO mapred.JobClient:  map 100% reduce 22%
12/06/01 18:19:23 INFO mapred.JobClient:  map 100% reduce 100%
12/06/01 18:19:28 INFO mapred.JobClient: Job complete: job_201206011229_0008
12/06/01 18:19:28 INFO mapred.JobClient: Counters: 29
12/06/01 18:19:28 INFO mapred.JobClient:   Job Counters 
12/06/01 18:19:28 INFO mapred.JobClient:     Launched reduce tasks=1
12/06/01 18:19:28 INFO mapred.JobClient:     SLOTS_MILLIS_MAPS=22810
12/06/01 18:19:28 INFO mapred.JobClient:     Total time spent by all reduces waiting after reserving slots (ms)=0
12/06/01 18:19:28 INFO mapred.JobClient:     Total time spent by all maps waiting after reserving slots (ms)=0
12/06/01 18:19:28 INFO mapred.JobClient:     Launched map tasks=3
12/06/01 18:19:28 INFO mapred.JobClient:     Data-local map tasks=3
12/06/01 18:19:28 INFO mapred.JobClient:     SLOTS_MILLIS_REDUCES=14345
12/06/01 18:19:28 INFO mapred.JobClient:   File Output Format Counters 
12/06/01 18:19:28 INFO mapred.JobClient:     Bytes Written=880838
12/06/01 18:19:28 INFO mapred.JobClient:   FileSystemCounters
12/06/01 18:19:28 INFO mapred.JobClient:     FILE_BYTES_READ=2214849
12/06/01 18:19:28 INFO mapred.JobClient:     HDFS_BYTES_READ=3671878
12/06/01 18:19:28 INFO mapred.JobClient:     FILE_BYTES_WRITTEN=3775339
12/06/01 18:19:28 INFO mapred.JobClient:     HDFS_BYTES_WRITTEN=880838
12/06/01 18:19:28 INFO mapred.JobClient:   File Input Format Counters 
12/06/01 18:19:28 INFO mapred.JobClient:     Bytes Read=3671517
12/06/01 18:19:28 INFO mapred.JobClient:   Map-Reduce Framework
12/06/01 18:19:28 INFO mapred.JobClient:     Map output materialized bytes=1474341
12/06/01 18:19:28 INFO mapred.JobClient:     Map input records=77932
12/06/01 18:19:28 INFO mapred.JobClient:     Reduce shuffle bytes=1207328
12/06/01 18:19:28 INFO mapred.JobClient:     Spilled Records=255962
12/06/01 18:19:28 INFO mapred.JobClient:     Map output bytes=6076095
12/06/01 18:19:28 INFO mapred.JobClient:     CPU time spent (ms)=12100
12/06/01 18:19:28 INFO mapred.JobClient:     Total committed heap usage (bytes)=516882432
12/06/01 18:19:28 INFO mapred.JobClient:     Combine input records=629172
12/06/01 18:19:28 INFO mapred.JobClient:     SPLIT_RAW_BYTES=361
12/06/01 18:19:28 INFO mapred.JobClient:     Reduce input records=102322
12/06/01 18:19:28 INFO mapred.JobClient:     Reduce input groups=82335
12/06/01 18:19:28 INFO mapred.JobClient:     Combine output records=102322
12/06/01 18:19:28 INFO mapred.JobClient:     Physical memory (bytes) snapshot=605229056
12/06/01 18:19:28 INFO mapred.JobClient:     Reduce output records=82335
12/06/01 18:19:28 INFO mapred.JobClient:     Virtual memory (bytes) snapshot=2276663296
12/06/01 18:19:28 INFO mapred.JobClient:     Map output records=629172

PS:目前,我正在使用一个小型数据集,其中快速压缩和解压缩并不重要.但是,一旦我有一个工作流程,我将使用大型数据集加载它.

Answer 1

如果 snappy 的共享库 (.so) 不在LD_LIBARAY_PATH/上，您将看到此错误消息java.library.path。如果您已将库安装在正确的位置，那么您应该不会看到上述错误消息。

如果您确实将 .so 安装在与 hadoop 本机库 ( libhadoop.so) 相同的文件夹中，那么上述“错误”可能与您提交作业的节点有关（就像您所说，您的作业不会出错并且这看起来像客户端的一条消息）。

您能否分享您的作业配置的一些详细信息（您在其中配置输出格式以及相关的压缩选项）。