[TEZ-1524] getDAGStatus seems to fork out the entire JVM on non-secure clusters

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.5.0
• Fix Version/s: 0.5.1
• Assignee: Gopal Vijayaraghavan
• Reporter: Gopal Vijayaraghavan
• Created: 29/Aug/14 19:39
• Updated: 02/Oct/14 21:40
• Resolved: 12/Sep/14 22:06

Description

Tracked down a consistent fork() call to

	at org.apache.hadoop.util.Shell.runCommand(Shell.java:505)
	at org.apache.hadoop.util.Shell.run(Shell.java:418)
	at org.apache.hadoop.util.Shell$ShellCommandExecutor.execute(Shell.java:650)
	at org.apache.hadoop.util.Shell.execCommand(Shell.java:739)
	at org.apache.hadoop.util.Shell.execCommand(Shell.java:722)
	at org.apache.hadoop.security.ShellBasedUnixGroupsMapping.getUnixGroups(ShellBasedUnixGroupsMapping.java:83)
	at org.apache.hadoop.security.ShellBasedUnixGroupsMapping.getGroups(ShellBasedUnixGroupsMapping.java:52)
	at org.apache.hadoop.security.JniBasedUnixGroupsMappingWithFallback.getGroups(JniBasedUnixGroupsMappingWithFallback.java:50)
	at org.apache.hadoop.security.Groups.getGroups(Groups.java:139)
	at org.apache.hadoop.security.UserGroupInformation.getGroupNames(UserGroupInformation.java:1409)
	at org.apache.tez.dag.api.client.rpc.DAGClientAMProtocolBlockingPBServerImpl.getRPCUserGroups(DAGClientAMProtocolBlockingPBServerImpl.java:75)
	at org.apache.tez.dag.api.client.rpc.DAGClientAMProtocolBlockingPBServerImpl.getDAGStatus(DAGClientAMProtocolBlockingPBServerImpl.java:102)
	at org.apache.tez.dag.api.client.rpc.DAGClientAMProtocolRPC$DAGClientAMProtocol$2.callBlockingMethod(DAGClientAMProtocolRPC.java:7375)

hitesh - would it make sense to cache this at all?