[HIVE-16873] Remove Thread Cache From Logging

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 3.0.0
• Component/s: Metastore
• Flags: Patch
• Assignee: David Mollitor
• Reporter: David Mollitor
• Created: 09/Jun/17 20:15
• Updated: 23/May/18 00:00
• Resolved: 14/Aug/17 20:44

Description

In org.apache.hadoop.hive.metastore.HiveMetaStore we have a Formatter class (and its buffer) tied to every thread.

This Formatter is for logging purposes. I would suggest that we simply let let the logging framework itself handle these kind of details and ditch the buffer per thread.

    public static final String AUDIT_FORMAT =
        "ugi=%s\t" + // ugi
            "ip=%s\t" + // remote IP
            "cmd=%s\t"; // command
    public static final Logger auditLog = LoggerFactory.getLogger(
        HiveMetaStore.class.getName() + ".audit");
    private static final ThreadLocal<Formatter> auditFormatter =
        new ThreadLocal<Formatter>() {
          @Override
          protected Formatter initialValue() {
            return new Formatter(new StringBuilder(AUDIT_FORMAT.length() * 4));
          }
        };

...

    private static final void logAuditEvent(String cmd) {
      final Formatter fmt = auditFormatter.get();
      ((StringBuilder) fmt.out()).setLength(0);

      String address = getIPAddress();
      if (address == null) {
        address = "unknown-ip-addr";
      }

      auditLog.info(fmt.format(AUDIT_FORMAT, ugi.getUserName(),
          address, cmd).toString());
    }