[HDFS-8890] Allow admin to specify which blockpools the balancer should run on

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.8.0, 3.0.0-alpha1
• Component/s: balancer & mover
• Hadoop Flags: Reviewed

Release Note

Adds a new blockpools flag to the balancer. This allows admins to specify which blockpools the balancer will run on.
Usage:
-blockpools <comma-separated list of blockpool ids>
The balancer will only run on blockpools included in this list.

• Assignee: Chris Trezzo
• Reporter: Chris Trezzo
• Created: 12/Aug/15 21:51
• Updated: 30/Aug/16 01:29
• Resolved: 02/Sep/15 23:02

Description

Currently the balancer runs on all blockpools. Allow an admin to run the balancer on a set of blockpools. This will enable the balancer to skip blockpools that should not be balanced. For example, a tmp blockpool that has a large amount of churn.

An example of the command line interface would be an additional flag that specifies the blockpools by id:

-blockpools BP-6299761-10.55.116.188-1415904647555,BP-47348528-10.51.120.139-1415904199257

Issue Links

• breaks: HDFS-9761 Rebalancer sleeps too long between iterations
• relates to: HDFS-9008 Balancer#Parameters class could use a builder pattern