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https://issues.apache.org/jira/browse/HBASE-18771?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16159582#comment-16159582
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Ashu Pachauri commented on HBASE-18771:
---------------------------------------

On a parallel note, echoing everyone else's opinion here that 
HStore#refreshStoreFiles should never be triggered for primary region replicas. 
This not only indicates an underlying problem (FNFE on scan path) but also may 
cause one to silently overlook some nasty dataloss scenarios.

> Incorrect StoreFileRefresh leading to split and compaction failures
> -------------------------------------------------------------------
>
>                 Key: HBASE-18771
>                 URL: https://issues.apache.org/jira/browse/HBASE-18771
>             Project: HBase
>          Issue Type: Bug
>    Affects Versions: 1.3.1
>            Reporter: Abhishek Singh Chouhan
>            Assignee: Abhishek Singh Chouhan
>            Priority: Blocker
>             Fix For: 1.4.0, 1.3.2, 1.5.0
>
>         Attachments: HBASE-18771.branch-1.3.001.patch, 
> HBASE-18771.branch-1.3.002.patch, HBASE-18771.branch-1.3.003.patch, 
> HBASE-18771.master.001.patch
>
>
> We ran into issues of compaction and split failures with 1.3 similar to 
> HBASE-18186 and HBASE-17406. Here's what i believe is happening -
> Lets say we have 4 store files that are compacted to form a new one. At this 
> point we now have 5 store files, however only 1(the newly formed) is open now 
> for the store and rest are waiting to get archived by HFileArchiver
> Now before the files are archived we get a FNFE in a scanner. This results in 
> HRegion.RegionScannerImpl.handleFileNotFound(FileNotFoundException fnfe) 
> being called which results in region.refreshStoreFiles(true) -> 
> HStore.refreshStoreFiles()
> HStore.refreshStoreFiles now checks the hdfs dir and adds the previously 
> compacted files back to the store, however these files are also present in 
> StoreFileManager's compactedFiles list. Now at this point HFileArchiver runs, 
> checks compactedFiles list and moves these files into the archive directory. 
> Now when compaction runs it gets:
> 2017-09-04 12:30:13,899 ERROR [ctions-1504505399609] 
> regionserver.CompactSplitThread - Compaction selection failed regionName = 
> xxxx, storeName = 0, priority = 26, time = 1504528213899
> java.io.FileNotFoundException: File does not exist: hdfs://xxxx
>         at 
> org.apache.hadoop.hdfs.DistributedFileSystem$23.doCall(DistributedFileSystem.java:1337)
>         at 
> org.apache.hadoop.hdfs.DistributedFileSystem$23.doCall(DistributedFileSystem.java:1329)
>         at 
> org.apache.hadoop.fs.FileSystemLinkResolver.resolve(FileSystemLinkResolver.java:81)
>         at 
> org.apache.hadoop.hdfs.DistributedFileSystem.getFileStatus(DistributedFileSystem.java:1329)
>         at 
> org.apache.hadoop.fs.FilterFileSystem.getFileStatus(FilterFileSystem.java:422)
>         at 
> org.apache.hadoop.hbase.regionserver.StoreFileInfo.getReferencedFileStatus(StoreFileInfo.java:342)
>         at 
> org.apache.hadoop.hbase.regionserver.StoreFileInfo.getFileStatus(StoreFileInfo.java:355)
>         at 
> org.apache.hadoop.hbase.regionserver.StoreFileInfo.getModificationTime(StoreFileInfo.java:360)
>         at 
> org.apache.hadoop.hbase.regionserver.StoreFile.getModificationTimeStamp(StoreFile.java:325)
>         at 
> org.apache.hadoop.hbase.regionserver.StoreUtils.getLowestTimestamp(StoreUtils.java:63)
>         at 
> org.apache.hadoop.hbase.regionserver.compactions.RatioBasedCompactionPolicy.shouldPerformMajorCompaction(RatioBasedCompactionPolicy.java:65)
>         at 
> org.apache.hadoop.hbase.regionserver.compactions.SortedCompactionPolicy.selectCompaction(SortedCompactionPolicy.java:82)
>         at 
> org.apache.hadoop.hbase.regionserver.DefaultStoreEngine$DefaultCompactionContext.select(DefaultStoreEngine.java:107)
>         at 
> org.apache.hadoop.hbase.regionserver.HStore.requestCompaction(HStore.java:1679)
> Similarly if a split happens after archival we fail after PONR while opening 
> daughter regions due to FNFE. This results in parent offline and daughters 
> also in a limbo since they're unable to open. Since we get the error after 
> PONR we also end up aborting the RS.



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