Thanks for the reply. I agree about the eventual consistency feature but in "addition" I'm trying to have an oversight if there is a slowness between nodes in a cluster meaning sometimes "some" network slowness won't translate in CA slowness and sometimes it will. I guess I'm looking for a process that tells me what the actual travel time between CA Node A and B is.
Here is very simple way how the same is done with SQL Server replication (sorry to wonder off into the RDBMS world): I insert a single timestamp into a small table and let SQL server replicate it to nodes. Upon arrival on each node the insert will automatically generate a default timestamp value into the same table/row. Taking the diff between original inserted (source) and default insert (target) timestamp I know precisely how long it took to push that content along within SQL Server. On Tue, May 24, 2011 at 11:46 PM, Aaron Morton <aa...@thelastpickle.com>wrote: > Once the cluster has returned to the client you know the write has been > committed to Consistency Level number of nodes. > > i.e. If you send an insert using QUORUM consistency to a cluster with > Replication Factor 3, and you get a non error response you know the write > has occurred on at least 2 nodes (one may be the one the client is connected > to.) > > After the initial request has completed it's up the "Eventual Consistency" > features of Read Repair, Hinted Handoff and Anti-Entropy to distribute > changes. > > Does that help or are you thinking of something else? > > ----------------- > Aaron Morton > Freelance Cassandra Developer > @aaronmortonhttp://www.thelastpickle.com > > > On 25 May, 2011,at 03:11 PM, Stephan Pfammatter <steplmi4...@gmail.com> > wrote: > > What’s the recommended way of measuring latency between nodes in a cluster? > > > By that I’m not referring to read/write latency for a given KS/CF. > > Basically I want to inject a row in a node A and want to see how long it > takes to get to node B (assuming proper RF is set). > > > I have already some network monitoring in our windows environment between > my distributed nodes in place. But I still would like to get a handle on how > a potential network and/or cassandra slowness affects inter-node latency. > Maybe there is a tool/cmd that I'm not aware of? Tx. > >
