NCache 4.6 - Online Documentation


With Microsoft restructuring ASP.NET 4 to ASP.NET Core, NCache has introduced Sessions State Management for ASP.NET Core to provide support with the new architecture. NCache provides flexible options to combine sessions with NCache’s enhanced caching capabilities, to boost performance as a whole. You can now store the default ASP.NET Core sessions within NCache or use NCache’s Session Management Services through extension methods on the ASP.NET Core modules to create and store custom configured sessions that utilize NCache.

NCache Session Properties

Exclusive Session Locking:  NCache Session Management enhances ASP.NET Core Sessions by providing exclusive session locking to avoid deadlock and data integrity being compromised. Locking is configurable and by default is off.
Locking Release Retry: If an exclusive lock is used, locking retries are also configured. In case of concurrent requests, lock release is tried a configured number of times.
Location Affinity: NCache’s Session Management Services provide Location Affinity which manages ASP.NET Core Sessions across multiple web farms which are geographically separated. For Location Affinity, one 'primary' and one or more 'secondary' caches have to be specified for each web farm. The primary cache will be used for all local traffic, in local region and secondary cache(s) are of distant geographical regions. These are configured in web.config.
Cluster Topologies: For sessions, different clustering topologies offered by NCache can be used. Replicated topology offers load balancing of client so that the ASP.NET Core application does not suffer during intensive traffic. If partitioned-replicated cache is used, it provides higher scalability and reliability to the application and performs faster transactions.
Reliability:  By default, a session is stored in-memory of an ASP.NET process. If the process recycles or an application server goes down, session data is lost. With NCache, session data is stored outside the ASP.NET process, in a cache cluster. Any cache topology can be opted to meet the needs of reliability. So in case of application server unavailability, session data remains available when the ASP.NET process recycles back or application server becomes live again.
Scalability: NCache Session uses in-memory cache as storage, where a clustered cache provides even better scalability. Working in a clustered environment allows adding more servers to session cluster at runtime; this results in more scalability and reliability for the application. Hence ASP.NET session clustering for web farms is faster and more scalable than storing them in a database.
Availability, Load Balancing, Fault Tolerance: In a web farm environment, using NCache with ASP.NET Core Sessions provides better fault tolerance, keeping session data available at all server nodes in a clustered cache. This also results handling larger load because sessions can be distributed to multiple servers in the farm.
Session Lookup in Cache Made Easy: All session data in cache can be retrieved in a single call through HttpContext.Session in ASP.NET Core.
Better Performance:  Session data being stored in in-memory cache, closer to the ASP.NET application, yields maximum performance.


ASP.NET Core works on the dependency injection, to allow loose coupling and more flexibility. The server is created within the application and uses the Startup class containing user-specified request handling definitions and configurations for the services. For more detail on the Startup class and its components, please refer to the ASP.NET Core documentation.

Startup class

The Startup class contains two methods:
IApplicationBuilder app, IHostingEnvironment env,
ILoggerFactory loggerFactory
Contains the user defined middleware logic before the logic layer is called where the session is being used. This takes care of HTTP request handling of the application. You can add middleware components to an instance of the IApplicationBuilder class to configure the request, like using MVC as a handler for the requests.
IServiceCollection services
Contains the configurations for the services that are provided for HTTP request handling. Hence, this method is called before Configure(). The configuration is provided in the appsettings.json file.
NCache provides ASP.NET Core support in two ways – you can either use NCache’s Session Management Services instead of ASP.NET Core Sessions or use ASP.NET Core Sessions with NCache distributed caching.
See Also