[HBASE-2358] Store doReconstructionLog will fail if oldlogfile.log is empty and won't load region

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.20.3
• Fix Version/s: 0.20.4, 0.90.0
• Component/s: regionserver

Environment

Any

• Hadoop Flags: Reviewed
• Assignee: Cosmin Lehene
• Reporter: Cosmin Lehene
• Due: 23/Mar/10
• Created: 22/Mar/10 18:01
• Updated: 12/Oct/12 06:15
• Resolved: 22/Mar/10 21:40

Description

doReconstructionLog doesn't handle empty files correctly:

    FileStatus stat = this.fs.getFileStatus(reconstructionLog);
    if (stat.getLen() <= 0) {
      LOG.warn("Passed reconstruction log " + reconstructionLog +
        " is zero-length. Deleting existing file");
       fs.delete(reconstructionLog, false);
      return -1;
    }

Notice it actually compares the length of the array instead of the file length.

It should call getLen() and delete the file afterwards

   FileStatus stat = this.fs.getFileStatus(reconstructionLog);
    if (stat.getLen() <= 0) {
      LOG.warn("Passed reconstruction log " + reconstructionLog +
        " is zero-length. Deleting existing file");
       fs.delete(reconstructionLog, false);
      return -1;
    }

Also. This is a situation that shouldn't happen as an empty oldlogfile.log should be deleted when HMaster does the split in HLog.splitLog().
I couldn't figure what would make it leave it there as I also see in the logs that other empty logs are deleted. This might expose a thornier situation.

Issue Links

• relates to: HBASE-1994 Master will lose hlog entries while splitting if region has empty oldlogfile.log