[YARN-2914] Potential race condition in Singleton implementation of SharedCacheUploaderMetrics, CleanerMetrics, ClientSCMMetrics

• Type: Sub-task
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.6.0
• Fix Version/s: 2.7.0
• Hadoop Flags: Reviewed
• Assignee: Varun Saxena
• Reporter: Ted Yu
• Created: 01/Dec/14 20:58
• Updated: 24/Apr/15 23:17
• Resolved: 15/Dec/14 20:02

Description

  public static ClientSCMMetrics getInstance() {
    ClientSCMMetrics topMetrics = Singleton.INSTANCE.impl;
    if (topMetrics == null) {
      throw new IllegalStateException(

getInstance() doesn't hold lock on Singleton.this
This may result in IllegalStateException being thrown prematurely.

ctrezzo reported that SharedCacheUploaderMetrics has also same kind of race condition.