[ https://issues.apache.org/jira/browse/LENS-619?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Himanshu Gahlaut updated LENS-619: ---------------------------------- Summary: Applying Query Launching Constraints before allowing a query to be launched (was: Applying Query Running Constraint before allowing a query to run) > Applying Query Launching Constraints before allowing a query to be launched > --------------------------------------------------------------------------- > > Key: LENS-619 > URL: https://issues.apache.org/jira/browse/LENS-619 > Project: Apache Lens > Issue Type: New Feature > Reporter: Himanshu Gahlaut > Assignee: Himanshu Gahlaut > > [June 23. 2015]: > This is the refined model after knowledge crunching: > Lens will always accept a new query from a user and put it in a scheduling > queue for processing. > Next candidate query picked up from scheduling queue for processing will be > run only if a query running constraint evaluated on running queries and > candidate query allows the candidate query to be run, otherwise the candidate > query will be moved to waiting queries list. > When any running query is finished, result of evaluation of query constraint > might change, waiting queries might become eligible to be run, hence waiting > queries will be moved back to scheduling queue to be re-processed. > Waiting Queries will be persisted across server restarts. > [Initial thought] (Not in work): Fair Usage Policy for using Lens > After a user has used the lens system beyond fair usage policy, he will get > lens features in degraded mode. > One of the forms of fair usage policy could be that at any point in time only > N queries can be present in RUNNING state for a user. > If N queries of a user are in RUNNING state, then a new query submitted by > same user will stay in QUEUED state until one of the N queries in RUNNING > state have moved to SUCCESSFUL, FAILED, OR CANCELLED state. -- This message was sent by Atlassian JIRA (v6.3.4#6332)