[HDFS-1676] DateFormat.getDateTimeInstance() is very expensive, we can cache it to improve performance

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Not A Problem
• Affects Version/s: 0.21.0
• Component/s: balancer & mover
• Labels: newbie
• Assignee: Unassigned
• Reporter: Xiaoming Shi
• Created: 01/Mar/11 02:22
• Updated: 28/Jul/15 00:34
• Resolved: 28/Jul/15 00:34

Description

In the file:

./hadoop-0.21.0/hdfs/src/java/org/apache/hadoop/hdfs/server/balancer/Balancer.java line:1520

In the while loop, DateFormat.getDateTimeInstance()is called in each iteration. We can cache the result by moving it outside the loop or adding a class member.

This is similar to the Apache bug https://issues.apache.org/bugzilla/show_bug.cgi?id=48778