TO start, I'd try to figure out what your slowdown is. Surely GCP has far, far more than 17Mbps available. You don't want to cut it close on this, because for stuff like repairs, rebuilds, interruptions, etc you'll want to be able to catch up and not just keep up. Generally speaking, Cassandra defers a lot of work and if you get behind when you're already at the limit of performance it's going to deteriorate badly.
Whether it's synchronous or async will depend on the query type for the write (ALL, LOCAL_QUORUM, etc) On Tue, Jan 26, 2021 at 6:37 PM MyWorld <timeplus.1...@gmail.com> wrote: > Hi, > We have a cluster with one Data Center of 3 nodes in GCP-US(RF=3).Current > apache cassandra version 3.11.6. We are planning to add one new Data Center > of 3 nodes in GCP-India. > > At peak hours, files generation in commit logs at GCP-US side on one node > is around 1 GB per minute (i.e 17+ mbps). > > Currently the file transfer speed from GCP US to India is 9 mbps. > > So, with this speed, is it possible in cassandra to perform asynchronous > write in new DC(India)? > Also, is there any compression technique which cassandra applies while > transferring data across DC? > > *My assumption *: All 3 coordinator nodes in US will be responsible for > transfering 1/3rd data to new DC. So, at peak time only 1GB/3 is what each > node has to sync. > Please let me know is my assumption right? If yes, what will happen if > data generated in commit log per node increase to 3 GB per minute tomorrow. > > Regards, > Ashish > >
