Product Comparisons: Subversion Clustering

Subversion Clustering vs. Shared Disk & Shared Memory Clustering:

• Subversion Clustering's approach is truly shared-nothing. There is no sharing of disk, memory or CPU between servers in a cluster so there's no single point of failure or performance bottleneck. In addition, WANdisco's unique replication technology turns the servers in a cluster into mirrors of each other, achieving continuous hot backup by default.
• Although the same write operations occur on every server in a cluster, near linear scaling is achieved. This is due to the fact that 80-90% of the operations against a Subversion server are typically read operations and Subversion Clustering distributes the load for read operations across all of the servers in a cluster. This has the effect of freeing up resources in each server to support write operations, so that write performance also improves.
• Intelligent load balancing capabilities optimize performance for end users by taking each server's current load into account before routing requests, rather than relying on simplistic round-robin approaches. If one of the servers in the cluster goes down, users will automatically fail over to another available server. When a server is brought back online it recovers automatically from the other servers in the cluster.
• Subversion Clustering's automatic recovery features also allow servers to be taken offline for maintenance without disrupting user access to the remaining servers. Many clustering solutions require all of the servers in a cluster to be brought down, just to take one server offline for maintenance, and recovery requires manual intervention.
• WANdisco's transparent implementation approach means that Subversion's functionality doesn't change, so there's no user retraining.