hadoop-common-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Doug Cutting <cutt...@apache.org>
Subject Re: Many Checksum Errors
Date Wed, 02 May 2007 16:23:13 GMT
Do you have ECC memory on your nodes?  Nodes without ECC have been known 
to trigger high rates of checksum errors.

Doug

Dennis Kubes wrote:
> All,
> 
> We are continually experiencing checksum errors when running some jobs 
> under heavy load (specifically merging segments or crawldbs).  I am lost 
> as to whether this is a hardware or software problem.  Two questions, 
> one is anyone else experiencing a large number of checksum type errors 
> on big clusters?  Two, does anyone know if this is hardware or software 
> related?  Here are some examples.
> 
> Dennis Kubes
> 
> 
> org.apache.hadoop.fs.ChecksumException: Checksum error: 
> /d01/hadoop/mapred/local/task_0042_m_001905_0/spill0.out at 79597056
>     at 
> org.apache.hadoop.fs.ChecksumFileSystem$FSInputChecker.verifySum(ChecksumFileSystem.java:258)

> 
>     at 
> org.apache.hadoop.fs.ChecksumFileSystem$FSInputChecker.readBuffer(ChecksumFileSystem.java:211)

> 
>     at 
> org.apache.hadoop.fs.ChecksumFileSystem$FSInputChecker.read(ChecksumFileSystem.java:167)

> 
>     at 
> org.apache.hadoop.fs.FSDataInputStream$PositionCache.read(FSDataInputStream.java:41)

> 
>     at java.io.BufferedInputStream.fill(BufferedInputStream.java:218)
>     at java.io.BufferedInputStream.read1(BufferedInputStream.java:256)
>     at java.io.BufferedInputStream.read(BufferedInputStream.java:313)
>     at java.io.DataInputStream.readFully(DataInputStream.java:176)
>     at java.io.DataInputStream.readFully(DataInputStream.java:152)
>     at 
> org.apache.hadoop.io.SequenceFile$UncompressedBytes.reset(SequenceFile.java:427) 
> 
>     at 
> org.apache.hadoop.io.SequenceFile$UncompressedBytes.access$700(SequenceFile.java:414)

> 
>     at 
> org.apache.hadoop.io.SequenceFile$Reader.nextRawValue(SequenceFile.java:1669) 
> 
>     at 
> org.apache.hadoop.io.SequenceFile$Sorter$SegmentDescriptor.nextRawValue(SequenceFile.java:2585)

> 
>     at 
> org.apache.hadoop.io.SequenceFile$Sorter$MergeQueue.next(SequenceFile.java:2356) 
> 
>     at 
> org.apache.hadoop.io.SequenceFile$Sorter.writeFile(SequenceFile.java:2230)
>     at 
> org.apache.hadoop.mapred.MapTask$MapOutputBuffer.mergeParts(MapTask.java:517) 
> 
>     at org.apache.hadoop.mapred.MapTask.run(MapTask.java:191)
>     at 
> org.apache.hadoop.mapred.TaskTracker$Child.main(TaskTracker.java:1701)
> 
> 
> 
> Map output lost, rescheduling: getMapOutput(task_0042_m_000375_0,4) 
> failed :
> org.apache.hadoop.fs.ChecksumException: Checksum error: 
> /d01/hadoop/mapred/local/task_0042_m_000375_0/file.out at 20267008
>     at 
> org.apache.hadoop.fs.ChecksumFileSystem$FSInputChecker.verifySum(ChecksumFileSystem.java:258)

> 
>     at 
> org.apache.hadoop.fs.ChecksumFileSystem$FSInputChecker.readBuffer(ChecksumFileSystem.java:211)

> 
>     at 
> org.apache.hadoop.fs.ChecksumFileSystem$FSInputChecker.read(ChecksumFileSystem.java:167)

> 
>     at 
> org.apache.hadoop.fs.FSDataInputStream$PositionCache.read(FSDataInputStream.java:41)

> 
>     at java.io.BufferedInputStream.read1(BufferedInputStream.java:254)
>     at java.io.BufferedInputStream.read(BufferedInputStream.java:313)
>     at java.io.DataInputStream.read(DataInputStream.java:134)
>     at 
> org.apache.hadoop.mapred.TaskTracker$MapOutputServlet.doGet(TaskTracker.java:1932) 
> 
>     at javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
>     at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
>     at 
> org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:427)
>     at 
> org.mortbay.jetty.servlet.WebApplicationHandler.dispatch(WebApplicationHandler.java:475)

> 
>     at 
> org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:567)
>     at org.mortbay.http.HttpContext.handle(HttpContext.java:1565)
>     at 
> org.mortbay.jetty.servlet.WebApplicationContext.handle(WebApplicationContext.java:635)

> 
>     at org.mortbay.http.HttpContext.handle(HttpContext.java:1517)
>     at org.mortbay.http.HttpServer.service(HttpServer.java:954)
>     at org.mortbay.http.HttpConnection.service(HttpConnection.java:814)
>     at org.mortbay.http.HttpConnection.handleNext(HttpConnection.java:981)
>     at org.mortbay.http.HttpConnection.handle(HttpConnection.java:831)
>     at 
> org.mortbay.http.SocketListener.handleConnection(SocketListener.java:244)
>     at org.mortbay.util.ThreadedServer.handle(ThreadedServer.java:357)
>     at org.mortbay.util.ThreadPool$PoolThread.run(ThreadPool.java:534)
> 

Mime
View raw message