ok, when a coordinator node sends timeout to the client, does it mean all the replica nodes have stopped processing that specific query too? Or is it just the coordinator node that has stopped waiting for the replicas to return response?
On Tue, Oct 12, 2021 at 10:12 AM Jeff Jirsa <jji...@gmail.com> wrote: > It sends an exception to the client, it doesnt sever the connection. > > > On Tue, Oct 12, 2021 at 10:06 AM S G <sg.online.em...@gmail.com> wrote: > >> Do the timeout values only kill the connection with the client or send >> error to the client? >> Or do they also kill the corresponding query execution happening on the >> Cassandra servers (co-ordinator, replicas etc) ? >> >> On Tue, Oct 12, 2021 at 10:00 AM Jeff Jirsa <jji...@gmail.com> wrote: >> >>> The read and write timeout values do this today. >>> >>> >>> https://github.com/apache/cassandra/blob/trunk/conf/cassandra.yaml#L920-L943 >>> >>> >>> On Tue, Oct 12, 2021 at 9:53 AM S G <sg.online.em...@gmail.com> wrote: >>> >>>> Hello, >>>> >>>> Is there a way to stop long running queries in Cassandra (versions >>>> 3.11.x or 4.x) ? >>>> The use-case is to have some kind of a circuit breaker based on >>>> query-time that has exceeded the client's SLAs. >>>> Example: If server response is useless to the client after 10 ms, then >>>> we could >>>> have a *query_killing_timeout* set to 15 ms (where additional 5ms >>>> allows for some buffer). >>>> And when that much time has elapsed, Cassandra will kill the query >>>> execution automatically. >>>> >>>> If this is not possible in Cassandra currently, any chance we can do it >>>> outside of Cassandra, like >>>> a shell script that monitors such long running queries (through users >>>> table etc) and kills the >>>> OS-thread responsible for that query (Looks unsafe though as that might >>>> leave the DB in an inconsistent state) ? >>>> >>>> We are trying this as a proactive measure to safeguard our clusters >>>> from any rogue queries fired accidentally or maliciously. >>>> >>>> Thanks ! >>>> >>>>
