[HDFS-14635] Support to refresh the rack awareness dynamically

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 2.7.2
• Component/s: hdfs
• Assignee: Unassigned
• Reporter: liying
• Created: 08/Jul/19 06:23
• Updated: 08/Jul/19 18:06

Description

At present , there are two ways to load the rack script in the hadoop codes. The class ScriptBasedMapping is the cache way, and the class ScriptBasedMapping#RawScriptBasedMapping is the way that
it will load script every time（every request）。 The cache is the good way to implement this feature， because it consumes cpu performance if loading the script for every quest。But here's another question that is we cann't refresh the cache, so it is import to support to refresh the rack awareness dynamically.

Issue Links

• is related to: HDFS-11242 Add refresh cluster network topology operation to dfs admin