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cassandradatastax

Is creating a Cassandra session per client ok for low client count?

I am creating a tool that lets a user do CRUD operations on a Cassandra DB through a graphical user interface. I was first planning to have clients establish their own connection to the cluster and get a session each but after doing research everyone is saying that you should use only one session. Right now I have two solutions:

1. Use multiple sessions anyways, as I had planned first.

  • It is easy to setup, just have the tool call ISession session = cluster.Connect(); when the tool opens
  • It might be slow? I don't know, I don't think it will be slow with low client count
  • It might be dangerous, CRUD operations might do unintended behaviour? From what I could gather this is not the case
  • My employer might kill me for not following standards? If this solution is easy to understand and there are negligible issues I doubt this will happen.

2. Use a client-server connection and send CQL queries to the server to then send to the DB and then return results to the client.

  • I only need one session that will talk to the DB in the server
  • It is A LOT more work
  • A piece of hardware have to actually be maintained to run the server and if it goes down the tool can't be used
  • It might be slow because of an added layer of communication between client-server? I don't know
  • It will be harder to do right, I have to set up a network communication protocol that manages every case

3. A third solution I haven't thought/know about.

As an example lets say we have 10 clients working at the same time (I doubt there will be this many working on it at the same time) and because I am curious, consider if there was 100 clients at the same time.

I am really leaning towards solution 1. but I also really want a second opinion from someone experienced. So yeah, is it ok for me to use solution 1 or is that a mistake/dangerous? I am using DataStax C# Driver for Apache Cassandra version 3.4.1

UPDATE: Is it possible to serialize an ISession instance and send it to a client to be reconstructed and used? This would be the best of both worlds because then I could share a single process with multiple clients without having to setup a network protocol. Everytime a clients boots it just has to ask the server for the session instance and then use it as if it had been created in the host.

Solution

  • It's better to share the session inside the one process, but if you have multiple separate processes, then it's ok to have separate sessions if you keep number of clients relatively low. Please only note that usually driver opens connection to every node in cluster, until you explicitly override load balancing policy (but you need to do it only if you definitely know what you do).