Running a query with trace (`TRACING ON` in cqlsh) can give you a lot of the information for an individual request. There has been a ticket to track time in queue (https://issues.apache.org/jira/browse/CASSANDRA-8398) but no ones worked on it yet.
Chris On Tue, Aug 30, 2016 at 12:20 PM, Jun Wu <wuxiaomi...@hotmail.com> wrote: > Hi there, > > I'm very interested in the read/write path of Cassandra. > Specifically, I'd like to know the whole process when a read/write request > comes in. > > I noticed that for reach request it could go through multiple stages. > For example, for read request, it could be in ReadStage, > RequestResponseStage, ReadRepairStage. For each stage, actually it's a > queue and thread pool to serve the request. > > First question is how to track each request in which stage. > > Also I'm very interested int the waiting time for each request to be in > the queue, also the total queue in each stage. I noticed that in nodetool > tpstats will have this information. However, I may want to get the > real-time information of this, like print it out in the terminal. > > I'm wondering whether someone has hints on this. > > Thanks in advance! > > Jun > > >
