Ted Yu created HBASE-17462: ------------------------------ Summary: Investigate using sliding window for read/write request costs in StochasticLoadBalancer Key: HBASE-17462 URL: https://issues.apache.org/jira/browse/HBASE-17462 Project: HBase Issue Type: Improvement Reporter: Ted Yu
In the thread, http://search-hadoop.com/m/HBase/YGbbyUZKXWALkX1, Timothy was asking whether the read/write request costs in StochasticLoadBalancer should be calculated as rates. This makes sense since read / write load on region server tends to fluctuate over time. Using sliding window would reflect more recent trend in read / write load. Some factors to consider: The data structure used by StochasticLoadBalancer should be concise. The number of regions in a cluster can be expected to approach 1 million. We cannot afford to store long history of read / write requests in master. Efficiency of cost calculation should be high - there're many cost functions the balancer goes through, it is expected for each cost function to return quickly. Otherwise we would not come up with proper region movement plan(s) in time. -- This message was sent by Atlassian JIRA (v6.3.4#6332)