hadoop - HBase region over region 服务器负载不均衡

Question

我正在运行一个带有两个 HBase 0.94.7 区域服务器的小型集群。我发现区域服务器上的负载请求非常不平衡。从网络用户界面，我得到:

Region1:  numberOfOnlineRegions=1, usedHeapMB=26, maxHeapMB=3983
Region2:  numberOfOnlineRegions=22, usedHeapMB=44, maxHeapMB=3983

region2 作为 master 服务。我检查了负载平衡器是否打开。我在主日志中找到了一些日志:

INFO org.apache.hadoop.hbase.master.LoadBalancer: Skipping load balancing because balanced cluster; servers=2 regions=1 average=0.5 mostloaded=1 leastloaded=0
DEBUG org.apache.hadoop.hbase.master.LoadBalancer: Balance parameter: numRegions=10, numServers=2, max=5, min=5
INFO org.apache.hadoop.hbase.master.LoadBalancer: Calculated a load balance in 12ms. Moving 5 regions off of 1 overloaded servers onto 1 less loaded servers
DEBUG org.apache.hadoop.hbase.master.LoadBalancer: Balance parameter: numRegions=8, numServers=2, max=4, min=4
INFO org.apache.hadoop.hbase.master.LoadBalancer: Calculated a load balance in 0ms. Moving 4 regions off of 1 overloaded servers onto 1 less loaded servers
INFO org.apache.hadoop.hbase.master.LoadBalancer: Skipping load balancing because balanced cluster; servers=2 regions=1 average=0.5 mostloaded=1 leastloaded=0
INFO org.apache.hadoop.hbase.master.HMaster: balance hri=LogTable,\x00\x00\x01\xE8\x00\x00\x01@\x09\xB2\xBA4$\xC3Oe,1374591174086.65391b7a54e9c8e85a3d94bf7627fd20., src=region2,60020,1374587851008, dest=region1,60020,1374587851018
DEBUG org.apache.hadoop.hbase.master.AssignmentManager: Starting unassignment of region LogTable,\x00\x00\x01\xE8\x00\x00\x01@\x09\xB2\xBA4$\xC3Oe,1374591174086.65391b7a54e9c8e85a3d94bf7627fd20. (offlining)

从region2到region1好像负载无法均衡。不知道是不是配置问题？我应该在 region1 上检查什么参数？

谢谢

Answer 1

您是否使用了顺序行键，例如时间戳？如果是这种情况，您可能最终会遇到 RegionServer Hotspotting，从而在服务器上施加不均匀的负载。如果可以，请避免使用顺序键。如果不可能创建预拆分表。