Need advice about which tool to choose?Ask the StackShare community!
Cassandra vs VoltDB: What are the differences?
# Introduction
In this comparison, we will highlight the key differences between Cassandra and VoltDB, two popular databases in the industry.
1. **Data Model**: Cassandra is a wide-column store NoSQL database that uses a decentralized architecture, perfect for handling massive amounts of data across multiple nodes. On the other hand, VoltDB is an in-memory operational database that stores data in memory for faster processing, making it ideal for real-time applications where low-latency is crucial.
2. **Consistency**: Cassandra offers eventual consistency, meaning that updates to the database may take some time to propagate across all nodes, leading to potential data divergence temporarily. In contrast, VoltDB provides strong consistency, ensuring that all nodes have the same data at any given moment, making it more reliable for critical operations that require data accuracy.
3. **Scalability**: Cassandra provides linear scalability by adding more nodes to the cluster, allowing it to handle growing workloads effortlessly. VoltDB, on the other hand, scales vertically by adding more resources to the server, making it easier to manage for smaller deployments with lower hardware requirements.
4. **Use Case**: Cassandra is well-suited for applications requiring high availability, fault tolerance, and scalability, such as social media platforms and IoT devices. VoltDB, with its emphasis on real-time processing, is best suited for applications that demand ultra-low latency, such as financial trading platforms and telecommunications systems.
5. **Architecture**: Cassandra follows a masterless architecture where all nodes are equal, allowing for high availability and fault tolerance. In contrast, VoltDB utilizes a shared-nothing architecture where each node operates independently, minimizing inter-node communication overhead and ensuring rapid processing speed.
6. **Consolidation**: While Cassandra is designed for horizontal scaling across multiple nodes to handle vast amounts of data, VoltDB focuses on consolidating data processing in-memory on a single server, making it more suitable for real-time analytics and transactional workloads that require lightning-fast response times.
# Summary
In summary, Cassandra and VoltDB differ in their data models, consistency levels, scalability options, use cases, architectures, and approaches to data processing, making them suitable for distinct types of applications depending on specific requirements.
The problem I have is - we need to process & change(update/insert) 55M Data every 2 min and this updated data to be available for Rest API for Filtering / Selection. Response time for Rest API should be less than 1 sec.
The most important factors for me are processing and storing time of 2 min. There need to be 2 views of Data One is for Selection & 2. Changed data.
Scylla can handle 1M/s events with a simple data model quite easily. The api to query is CQL, we have REST api but that's for control/monitoring
Cassandra is quite capable of the task, in a highly available way, given appropriate scaling of the system. Remember that updates are only inserts, and that efficient retrieval is only by key (which can be a complex key). Talking of keys, make sure that the keys are well distributed.
By 55M do you mean 55 million entity changes per 2 minutes? It is relatively high, means almost 460k per second. If I had to choose between Scylla or Cassandra, I would opt for Scylla as it is promising better performance for simple operations. However, maybe it would be worth to consider yet another alternative technology. Take into consideration required consistency, reliability and high availability and you may realize that there are more suitable once. Rest API should not be the main driver, because you can always develop the API yourself, if not supported by given technology.
i love syclla for pet projects however it's license which is based on server model is an issue. thus i recommend cassandra
Pros of Cassandra
- Distributed119
- High performance98
- High availability81
- Easy scalability74
- Replication53
- Reliable26
- Multi datacenter deployments26
- Schema optional10
- OLTP9
- Open source8
- Workload separation (via MDC)2
- Fast1
Pros of VoltDB
- SQL + Java5
- In-memory database4
- A brainchild of Michael Stonebraker4
- Very Fast3
- NewSQL2
Sign up to add or upvote prosMake informed product decisions
Cons of Cassandra
- Reliability of replication3
- Size1
- Updates1