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  1. Apache Drill
  2. DRILL-1170 YARN support for Drill
  3. DRILL-4581

Various problems in the Drill startup scripts

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    Details

    • Type: Sub-task
    • Status: Closed
    • Priority: Minor
    • Resolution: Fixed
    • Affects Version/s: 1.6.0
    • Fix Version/s: 1.8.0
    • Component/s: Server
    • Labels:
      None

      Description

      Noticed the following in drillbit.sh:

      1) Comment: DRILL_LOG_DIR Where log files are stored. PWD by default.
      Code: DRILL_LOG_DIR=/var/log/drill or, if it does not exist, $DRILL_HOME/log

      2) Comment: DRILL_PID_DIR The pid files are stored. /tmp by default.
      Code: DRILL_PID_DIR=$DRILL_HOME

      3) Redundant checking of JAVA_HOME. drillbit.sh sources drill-config.sh which checks JAVA_HOME. Later, drillbit.sh checks it again. The second check is both unnecessary and prints a less informative message than the drill-config.sh check. Suggestion: Remove the JAVA_HOME check in drillbit.sh.

      4) Though drill-config.sh carefully checks JAVA_HOME, it does not export the JAVA_HOME variable. Perhaps this is why drillbit.sh repeats the check? Recommended: export JAVA_HOME from drill-config.sh.

      5) Both drillbit.sh and the sourced drill-config.sh check DRILL_LOG_DIR and set the default value. Drill-config.sh defaults to /var/log/drill, or if that fails, to $DRILL_HOME/log. Drillbit.sh just sets /var/log/drill and does not handle the case where that directory is not writable. Suggested: remove the check in drillbit.sh.

      6) Drill-config.sh checks the writability of the DRILL_LOG_DIR by touching sqlline.log, but does not delete that file, leaving a bogus, empty client log file on the drillbit server. Recommendation: use bash commands instead.

      7) The implementation of the above check is a bit awkward. It has a fallback case with somewhat awkward logic. Clean this up.

      8) drillbit.sh, but not drill-config.sh, attempts to create /var/log/drill if it does not exist. Recommended: decide on a single choice, implement it in drill-config.sh.

      9) drill-config.sh checks if $DRILL_CONF_DIR is a directory. If not, defaults it to $DRILL_HOME/conf. This can lead to subtle errors. If I use
      drillbit.sh --config /misspelled/path
      where I mistype the path, I won't get an error, I get the default config, which may not at all be what I want to run. Recommendation: if the value of DRILL_CONF_DRILL is passed into the script (as a variable or via --config), then that directory must exist. Else, use the default.

      10) drill-config.sh exports, but may not set, HADOOP_HOME. This may be left over from the original Hadoop script that the Drill script was based upon. Recomendation: export only in the case that HADOOP_HOME is set for cygwin.

      11) Drill-config.sh checks JAVA_HOME and prints a big, bold error message to stderr if JAVA_HOME is not set. Then, it checks the Java version and prints a different message (to stdout) if the version is wrong. Recommendation: use the same format (and stderr) for both.

      12) Similarly, other Java checks later in the script produce messages to stdout, not stderr.

      13) Drill-config.sh searches $JAVA_HOME to find java/java.exe and verifies that it is executable. The script then throws away what we just found. Then, drill-bit.sh tries to recreate this information as:
      JAVA=$JAVA_HOME/bin/java
      This is wrong in two ways: 1) it ignores the actual java location and assumes it, and 2) it does not handle the java.exe case that drill-config.sh carefully worked out.
      Recommendation: export JAVA from drill-config.sh and remove the above line from drillbit.sh.

      14) drillbit.sh presumably takes extra arguments like this:
      drillbit.sh -Dvar0=value0 --config /my/conf/dir start -Dvar1=value1 -Dvar2=value2 -Dvar3=value3
      The -D bit allows the user to override config variables at the command line. But, the scripts don't use the values.
      A) drill-config.sh consumes --config /my/conf/dir after consuming the leading arguments:
      while [ $# -gt 1 ]; do
      if [ "--config" = "$1" ]; then
      shift
      confdir=$1
      shift
      DRILL_CONF_DIR=$confdir
      else

      1. Presume we are at end of options and break
        break
        fi
        done
        B) drill-bit.sh will discard the var1:
        startStopStatus=$1 <-- grabs "start"
        shift
        command=drillbit
        shift <-- Consumes -Dvar1=value1
        C) Remaining values passed back into drillbit.sh:
        args=$@
        nohup $thiscmd internal_start $command $args
        D) Second invocation discards -Dvar2=value2 as described above.
        E) Remaining values are passed to runbit:
        "$DRILL_HOME"/bin/runbit $command "$@" start
        F) Where they again pass though drill-config. (Allowing us to do:
        drillbit.sh --config /first/conf --config /second/conf
        which is asking for trouble)
        G) And, the remaining arguments are simply not used:
        exec $JAVA -Dlog.path=$DRILLBIT_LOG_PATH -Dlog.query.path=$DRILLBIT_QUERY_LOG_PATH $DRILL_ALL_JAVA_OPTS -cp $CP org.apache.drill.exec.server.Drillbit

      15) The checking of command-line args in drillbit.sh is wrong:

      1. if no args specified, show usage
        if [ $# -lt 1 ]; then
        echo $usage
        exit 1
        fi
        ...
        . "$bin"/drill-config.sh

      But, note, that drill-config.sh handles:
      drillbit.sh --config /conf/dir
      Consuming those two arguments will leave no command argument. Thus, the no-argument check should be done AFTER consuming --config.

      16) As noted above, both drillbit.sh and runbit source drill-config.sh. But runbit is (apparently) only every called from drillbit.sh. Therefore, we do the same setup & check tasks twice. (In addition to reading --config twice as noted above.) Recommendation: omit the sourcing of drill-config.sh in runbit.

      17) The name of the drillbit.sh script is used in many messages. It is hardcoded, but appears to originally have been taken from $0:

      command=drillbit
      shift

      Recommended: get the name from the script, strip the directory, and strip the suffix. So, /foo/drillbit2.sh becomes drillbit2, \windir\drillbit2.bat becomes drillbit2.

      18) drillbit.sh creates a pid file to record the pid of the running Drillbit. However, the file is not deleted upon normal Drill exit. Better would be to remove this file on exit to keep things tidy.

      19) Similarly, when the stop command detects a pid file, but no running process with that pid, it prints a message saying so, but does not clean up the (unwanted) pid file. It should do so.

      20) The runbit script sets up Java options as follows:

      DRILL_ALL_JAVA_OPTS="$DRILLBIT_JAVA_OPTS $DRILL_JAVA_OPTS $SERVER_GC_OPTS"

      Presumably the DRILL_JAVA_OPTS are for all Drill apps (including the client) while DRILLBIT_JAVA_OPTS are for the server (drillbit).
      Since later Java options override earlier ones, more specific options (for the server) should come after more general ones (for all of Drill). So, order should be:

      DRILL_ALL_JAVA_OPTS="$DRILL_JAVA_OPTS $DRILLBIT_JAVA_OPTS $SERVER_GC_OPTS"

      21) The startup scripts go to great lengths to properly set up the logs. But, we allow drill-env.sh to override them.

      exec $JAVA -Dlog.path=$DRILLBIT_LOG_PATH -Dlog.query.path=$DRILLBIT_QUERY_LOG_PATH $DRILL_ALL_JAVA_OPTS ...

      The computed log properties come before the user-defined properties, and so user defined properties can override those log settings. The computed log settings are used to write log entries and should be considered "correct."
      Recommended: change option order as follows:

      exec $JAVA $DRILL_ALL_JAVA_OPTS -Dlog.path=$DRILLBIT_LOG_PATH -Dlog.query.path=$DRILLBIT_QUERY_LOG_PATH ...

      22) As above, but in sqlline:

      exec "$JAVA" $DRILL_SHELL_JAVA_OPTS $DRILL_JAVA_OPTS

      Should be:

      exec "$JAVA" $DRILL_JAVA_OPTS $DRILL_SHELL_JAVA_OPTS

      23) The implementations of each command unnecessarily pass along $command on internal calls:

      (start)
      nohup $thiscmd internal_start $command $args < /dev/null >> ${logout} 2>&1 &
      (internal_start)
      nice -n $DRILL_NICENESS "$DRILL_HOME"/bin/runbit \
      $command "$@" start >> "$logout" 2>&1 &

      Results in "drillbit drillbit start" being passed to runbit. Today, runbit does not use these arguments. But, if it did, it would get unncesssary clutter.

      24) Benign. The restart command passes $command uncessarily when calling the drillbit.sh script recursively:
      $thiscmd --config "${DRILL_CONF_DIR}" stop $command $args &
      $thiscmd --config "${DRILL_CONF_DIR}" start $command $args &

      results in drillbit.sh --conf ... stop drill bit

      25) The stop command removes a file using an undefined variable:
      rm -f "$DRILL_START_FILE"

      This variable is never defined in any of the startup scripts. If the user can define it, we should be checking if the variable is empty. Suggestion: remove this line.

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            • Assignee:
              paul-rogers Paul Rogers
              Reporter:
              paul-rogers Paul Rogers
              Reviewer:
              Abhishek Girish
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              Dates

              • Created:
                Updated:
                Resolved: