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Jordan West commented on CASSANDRA-14499: ----------------------------------------- {quote}disabling gosspi alone is insufficient, also need to disable native {quote} Agreed. I hadn't updated the description to reflect it but what I am working on does this as well. {quote}still not sure I buy the argument that it’s wrong to serve reads in this case - it may be true that some table is getting out of sync, but that doesn’t mean every table is, {quote} I agree it depends on the workload for each specific dataset but since we can't know which we have we have to assume it could get really out of sync. {quote}and we already have a mechanism to deal with nodes that can serve reads but not writes (speculating on the read repair). {quote} Even if we speculate we still attempt it. That work will always be for naught and being at quota is likely a prolonged state (the ways out of it take a while). {quote}If you don’t serve reads either, than any GC pause will be guaranteed to impact client request latency as we can’t soeculate around it in the common rf=3 case. {quote} This is true. But thats almost the same as losing a node because its disk has been filled up completely. If we have one unhealthy node we are another unhealthy node away from unavailability in the rf=3/quorum case. That said, I'll consider the reads more over the weekend. Its a valid concern. > node-level disk quota > --------------------- > > Key: CASSANDRA-14499 > URL: https://issues.apache.org/jira/browse/CASSANDRA-14499 > Project: Cassandra > Issue Type: New Feature > Reporter: Jordan West > Assignee: Jordan West > Priority: Major > > Operators should be able to specify, via YAML, the amount of usable disk > space on a node as a percentage of the total available or as an absolute > value. If both are specified, the absolute value should take precedence. This > allows operators to reserve space available to the database for background > tasks -- primarily compaction. When a node reaches its quota, gossip should > be disabled to prevent it taking further writes (which would increase the > amount of data stored), being involved in reads (which are likely to be more > inconsistent over time), or participating in repair (which may increase the > amount of space used on the machine). The node re-enables gossip when the > amount of data it stores is below the quota. > The proposed option differs from {{min_free_space_per_drive_in_mb}}, which > reserves some amount of space on each drive that is not usable by the > database. -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org