[HDFS-17285] RBF: Add a safe mode check period configuration

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 3.4.0
• Fix Version/s: 3.4.0
• Component/s: rbf
• Labels: pull-request-available
• Target Version/s: 3.4.0
• Hadoop Flags: Reviewed
• Assignee: liuguanghua
• Reporter: liuguanghua
• Created: 12/Dec/23 07:54
• Updated: 27/Jan/24 01:08
• Resolved: 21/Dec/23 04:23

Description

When dfsrouter start, it enters safe mode. And it will cost 1min to leave.

The log is blow:

14:35:23,717 INFO org.apache.hadoop.hdfs.server.federation.router.RouterSafemodeService: Leave startup safe mode after 30000 ms
14:35:23,717 INFO org.apache.hadoop.hdfs.server.federation.router.RouterSafemodeService: Enter safe mode after 180000 ms without reaching the State Store
14:35:23,717 INFO org.apache.hadoop.hdfs.server.federation.router.RouterSafemodeService: Entering safe mode
14:35:24,996 INFO org.apache.hadoop.hdfs.server.federation.router.RouterSafemodeService: Delaying safemode exit for 28721 milliseconds...
14:36:25,037 INFO org.apache.hadoop.hdfs.server.federation.router.RouterSafemodeService: Leaving safe mode after 61319 milliseconds

It depends on these configs.
DFS_ROUTER_SAFEMODE_EXTENSION 30s 
DFS_ROUTER_SAFEMODE_EXPIRATION 3min
DFS_ROUTER_CACHE_TIME_TO_LIVE_MS 1min  (it is the period for check safe mode)

Because in safe mode dfsrouter will reject write requests, so it should be shorter in check period if refreshCaches is done.  And we should remove DFS_ROUTER_CACHE_TIME_TO_LIVE_MS form RouterSafemodeService.

Issue Links

• links to: GitHub Pull Request #6347