[HDFS-8303] QJM should purge old logs in the current directory through FJM

• Type: Sub-task
• Status: Patch Available
• Priority: Major
• Resolution: Unresolved
• Labels: BB2015-05-TBR
• Assignee: István Fajth
• Reporter: Zhe Zhang
• Created: 30/Apr/15 18:25
• Updated: 21/Aug/19 15:49

Description

As the first step of the consolidation effort, QJM should call its FJM to purge the current directory.

The current QJM logic of purging current dir is very similar to FJM purging logic.

QJM:

 private static final List<Pattern> CURRENT_DIR_PURGE_REGEXES =
      ImmutableList.of(
        Pattern.compile("edits_\\d+-(\\d+)"),
        Pattern.compile("edits_inprogress_(\\d+)(?:\\..*)?"));
...
          long txid = Long.parseLong(matcher.group(1));
          if (txid < minTxIdToKeep) {
            LOG.info("Purging no-longer needed file " + txid);
            if (!f.delete()) {
...

FJM:

  private static final Pattern EDITS_REGEX = Pattern.compile(
    NameNodeFile.EDITS.getName() + "_(\\d+)-(\\d+)");
  private static final Pattern EDITS_INPROGRESS_REGEX = Pattern.compile(
    NameNodeFile.EDITS_INPROGRESS.getName() + "_(\\d+)");
  private static final Pattern EDITS_INPROGRESS_STALE_REGEX = Pattern.compile(
      NameNodeFile.EDITS_INPROGRESS.getName() + "_(\\d+).*(\\S+)");
...
    List<EditLogFile> editLogs = matchEditLogs(files, true);
    for (EditLogFile log : editLogs) {
      if (log.getFirstTxId() < minTxIdToKeep &&
          log.getLastTxId() < minTxIdToKeep) {
        purger.purgeLog(log);
      }
    }

I can see 2 differences:

1. Different regex in matching for empty/corrupt in-progress files. The FJM pattern makes more sense to me.
2. FJM verifies that both start and end txID of a finalized edit file to be old enough. This doesn't make sense because end txID is always larger than start txID

Issue Links

• is required by: HDFS-8178 QJM doesn't move aside stale inprogress edits files