[ZOOKEEPER-1616] time calculations should use a monotonic clock

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Assignee: Unassigned
• Reporter: Todd Lipcon
• Created: 09/Jan/13 00:35
• Updated: 11/Apr/15 21:44
• Resolved: 11/Apr/15 21:44

Description

We recently had an issue with ZooKeeper sessions acting strangely due to a bad NTP setup on a set of hosts. Looking at the code, ZK seems to use System.currentTimeMillis to measure durations or intervals in many places. This is bad since that time can move backwards or skip ahead by several minutes. Instead, it should use System.nanoTime (or a wrapper such as Guava's Stopwatch class)

Issue Links

• duplicates: ZOOKEEPER-1366 Zookeeper should be tolerant of clock adjustments