Enterprise Class Performance, Scalability, Availability and Backup for CVS
CVS Clustering eliminates the single point of failure and performance bottleneck of a central CVS server over a local area network. By combining WANdisco's unique replication technology and intelligent load balancing software, CVS can be deployed in an active-active cluster that delivers optimum performance, scalability and availability, with built-in continuous hot backup and automated recovery. Downtime and data loss are completely eliminated.
Dynamically balances workload across CVS servers at a single location over a LAN, or multiple locations over a WAN.
All servers in a cluster are fully readable and writeable and always in sync, making the cluster appear to end users as a single CVS server.
CVS Clustering has no single point of failure. There is no sharing of disk, CPU or memory between servers in a cluster. Even load balancers can be paired for redundancy using the resilient cluster option.
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.
When a network or server outage takes place, failover is transparent and immediate and recovery is automatic. Users experience no downtime or data loss, and the risk of human error is eliminated.
Automated failover and recovery capabilities can be used to take servers offline for maintenance without interrupting user access, making full 24-by-7 operation possible. When a server is brought back online after maintenance is complete, it resynchronizes automatically with the other servers in the cluster.
Connection draining allows existing tasks to be completed, while blocking new user connections before a server is taken offline for maintenance.
Hot deploy capability allows servers to be added to a cluster without any downtime.
CVS Clustering can be implemented stand-alone or in combination with CVS MultiSite.
What is CVS?
CVS is an open source version control system that stores and tracks changes made to any type of electronic data, including source code files, web pages, documents, or images. CVS has been available since 1989, and is still widely used today.
CVS Clustering vs. Shared Disk & Shared Memory Clustering:
CVS 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 CVS server are typically read operations and CVS 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.
CVS 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 CVS functionality doesn't change, so there's no user retraining.