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HBase Performance Optimization- Page2

By Dinesh

 

Refer Page 1 of this article @https://querydb.blogspot.com/2023/10/hbase-performance-optimization.html


Normally, we run multiple workloads on the cluster. This includes Analytical as well as API calls. This also involves read & write traffic as well...

HBase provides the following mechanisms for managing the performance of a cluster handling multiple workloads: . Quotas . Request Queues . Multiple-Typed Queues

Quotas

HBASE-11598 introduces RPC quotas, which allow you to throttle requests based on the following limits

  • Limit overall network throughput and number of RPC requests
  • Limit amount of storage used for table or namespaces
  • Limit number of tables for each namespace or user
  • Limit number of regions for each namespace
For this to work - 
  • Set the hbase.quota.enabled property in the hbase-site.xml file to true.
  • Enter the command to set the set the limit of the quota, type of quota, and to which entity to apply the quota. The command and its syntax are: $hbase_shell> set_quota TYPE =>
        For example - set_quota TYPE => THROTTLE, THROTTLE_TYPE => READ, TABLE => 'N1:T1', LIMIT => '2req/sec'



Request Queues

HBASE-10993 introduces such a system for deprioritizing long-running scanners. There are two types of queues, fifo and deadline. To configure the type of queue used, configure the hbase.ipc.server.callqueue.type property in hbase-site.xml. There is no way to estimate how long each request may take, so de-prioritization only affects scans, and is based on the number of “next” calls a scan request has made. An assumption is made that when you are doing a full table scan, your job is not likely to be interactive, so if there are concurrent requests, you can delay long-running scans up to a limit tunable by setting the hbase.ipc.server.queue.max.call.delay property. The slope of the delay is calculated by a simple square root of (numNextCall * weight) where the weight is configurable by setting the hbase.ipc.server.scan.vtime.weight property.


Multiple-Typed Queues

Set following properties - 
  • hbase.ipc.server.callqueue.handler.factor
  • hbase.ipc.server.callqueue.read.ratio
  • hbase.ipc.server.callqueue.scan.ratio


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