[YARN-9350] Change log level to WARN when ShellCommandExecutor.execute() occurs exception

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 3.1.0, 2.8.5
• Component/s: yarn
• Labels: easyfix
• Flags: Important
• Assignee: Unassigned
• Reporter: Anuhan Torgonshar
• Created: 07/Mar/19 01:08
• Updated: 07/Jul/19 14:42

Description

When method ShellCommandExecutor.execute() occurs exception , it has inconsistent log level practices in different places as following :

//hadoop-2.8.5-src\hadoop-yarn-project\hadoop-yarn\hadoop-yarn-common\src\main\java\org\apache\hadoop\yarn\util\WindowsBasedProcessTree.java
//log statement line number:69
//log level:error
try {
   shellExecutor.execute();
} catch (IOException e) {
   LOG.error(StringUtils.stringifyException(e));
} finally {
   String output = shellExecutor.getOutput();
   if (output != null &&
   output.contains("Prints to stdout a list of processes in the task")) {
   return true;
}

//hadoop-2.8.5-src\hadoop-common-project\hadoop-common\src\main\java\org\apache\hadoop\util\NodeHealthScriptRunner.java
//log statement line number:116
//log level:warn
try {
  shexec.execute();
} catch (ExitCodeException e) {
  ......
} catch (Exception e) {
   LOG.warn("Caught exception : " + e.getMessage());
   if (!shexec.isTimedOut()) {
     status = HealthCheckerExitStatus.FAILED_WITH_EXCEPTION;
   } else {
     status = HealthCheckerExitStatus.TIMED_OUT;
   }
   exceptionStackTrace = StringUtils.stringifyException(e);
} finally {
   ......
}

//hadoop-2.8.5-src\hadoop-yarn-project\hadoop-yarn\hadoop-yarn-server\hadoop-yarn-server-nodemanager\src\main\java\org\apache\hadoop\yarn\server\nodemanager\containermanager\linux\privileged\PrivilegedOperationExecutor.java
//log statement line number:179
//log level:warn
try {
   exec.execute();
   if (LOG.isDebugEnabled()) {
     LOG.debug("command array:");
     LOG.debug(Arrays.toString(fullCommandArray));
     LOG.debug("Privileged Execution Operation Output:");
     LOG.debug(exec.getOutput());
   }
} catch (ExitCodeException e) {
   ......
} catch (IOException e) {
LOG.warn("IOException executing command: ", e);
throw new PrivilegedOperationException(e);
}

There are 2 similar code snippets assign WARN level, when execute() occurs exception, simultaneously only 1 code snippet chooses ERROR level for same situation. Therefore, I think this one log statement is more likely to be assigned WARN level.