[ https://issues.apache.org/jira/browse/CASSANDRA-3518?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13154920#comment-13154920 ]
Chris Goffinet edited comment on CASSANDRA-3518 at 11/22/11 7:08 AM: --------------------------------------------------------------------- Radim, I know what the Request Scheduler is.. please read my ticket more carefully. {noformat} # Scheduler Options vary based on the type of scheduler # NoScheduler - Has no options # RoundRobin # - throttle_limit -- The throttle_limit is the number of in-flight # requests per client. Requests beyond # that limit are queued up until # running requests can complete. # The value of 80 here is twice the number of # concurrent_reads + concurrent_writes. {noformat} number of in-flight requests per client. I want to a) do this per user b) break it down so it's request/s not how many concurrent reads/writes in flight. was (Author: lenn0x): Radim, I know what the Request Scheduler is.. please read my ticket more carefully. # Scheduler Options vary based on the type of scheduler # NoScheduler - Has no options # RoundRobin # - throttle_limit -- The throttle_limit is the number of in-flight # requests per client. Requests beyond # that limit are queued up until # running requests can complete. # The value of 80 here is twice the number of # concurrent_reads + concurrent_writes. number of in-flight requests per client. I want to a) do this per user b) break it down so it's request/s not how many concurrent reads/writes in flight. > Back pressure users by request/s instead of concurrent reads/writes > ------------------------------------------------------------------- > > Key: CASSANDRA-3518 > URL: https://issues.apache.org/jira/browse/CASSANDRA-3518 > Project: Cassandra > Issue Type: Bug > Affects Versions: 1.0.2 > Reporter: Chris Goffinet > > We are running into use cases where it makes a lot of sense to have QoS at > the request level per user. Imagine this case: > I have a cluster that can do 100,000 req/s. But I want to limit the user to > only being able to do either 50,000 read or write/s per second in the > cluster. I rather give back pressure to the user then make the cluster fall > down because the user tried to take down my cluster. > Also another case we have is where you have experimental features and want to > give access to certain group of customers and let them run experiments on > data. You *dont* want them taking down the cluster, you rather make them fail > fast, or slow them down. If I could limit a user to N req/s for reads or > writes, instead of adding back pressure based on # of concurrent requests in > each stage, this would go a long way for us. > We have had a few incidents where spinning up new features caused unexpected > load and we couldn't stop them without turning the feature off. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira