Entity Framework (EF) Caching Configuration File

Note

This feature is only available in NCache Enterprise Edition. The efcaching.ncconf file is shipped with the NCache Entity Framework NuGet package.

Entity Framework Caching Config file, efcaching.ncconf, contains cache and caching policy related information used by NCache Entity Framework Caching provider. Some changes are required in efcaching.ncconf to run the Entity Framework application with NCache.

You can configure the following through efcaching.ncconf:

  • EF integration modes
  • Database synchronization
  • Cache item expiration
<configuration>
    <app-config app-id="EFCachingDemo" mode="analysis|caching">

        <analysis-policy log-path="" analysis-time="1min" cache-enable-threshold="1" default-expiration-type="Sliding" default-expiration-time="180sec" dbsyncdependency="false"/>

        <cache-policy-configuration database="none|sqlserver|oracle" cache-id="demoCache">
            <api-level-caching expiration-type="Sliding" enable="True" expiration-time="30sec" dbsyncdependency="False" resyncProviderName="EFResyncProvider"/> 

            <!--sql-query = "SELECT [Extent1].[CustomerID] AS [CustomerID],= @param_0"-->
            <query>
                <cache-query querytext="SELECT [Extent1].[OrderID] AS [OrderID], &lt; @param_0"/>
                <cache-policy vary-by-cache-param="param_0" expiration-type="Sliding" enabled="True" expiration-time="180sec" dbsyncdependency="False" resyncProviderName="EFResyncProvider">
            </query>
        </cache-policy-configuration>
    </app-config>
</configuration>

Properties

Member Description
app-id This ID is same as defined in app/web configuration file of application. Multiple app-ids can also be provided but their names must be unique in each case.
mode NCache Entity Framework Caching provider works under two modes. It can either be in "Analysis" or "Caching" mode.
Analysis Mode: This mode is used for monitoring the number of times each query executes and generates its report. Report contains the query text and the call count for each query. No caching is done at this mode.
  • log-path: The default path at which analysis log files will be generated is %NCHOME%\log-files\EFCachingAnalysisLogs\ (Windows) or /opt/ncache/log-files/EFCachingAnalysisLogs/ (Linux).
  • analysis-time: Time for which the analysis will run. The default value is 1 min.
  • cache-enable-threshold: Caching will automatically be enabled for queries whose call-count exceeds this threshold. The default value is 1.
  • default-expiration-type: Default expiration type for analyzed queries. The default type is Sliding, but you can also set Absolute as your default expiration type.
  • default-expiration-time: The default expiration time for analyzed queries. The default value is 180 sec (3 min).
  • dbsyncdependency: Determines whether to enable Database Dependency or not. The default value is False.

    Caching Mode: In this mode, the wrapping provider will cache the results of all the specified queries. Whenever an update is detected (either UPDATE, INSERT or DELETE) in a respective database, the provider invalidates the affected cache entries, by evicting all the cached queries which were dependent on any of the updated tables.

  • database: Database server where user's database resides.
  • cache-id: Specified cache name where query results are stored for fast access.
    		•
    api-level-caching This tag contains the configuration policies for queries, if they are not mentioned in the efcaching.ncconf file.
    query Query attributes including user-configurable list of queries that should be cached with their results. A particular query can be configured with its cache policy defined in cache policy tag. Cache query and cache policy are separated by dedicated tags. User can easily change policies from cache policy tag without facing any XML parsing error.
    cache-query For cache query, this tag is auto generated by Entity Framework Caching provider when the application is running in Analysis mode. For ease of understanding, commented SQL-query tag is added so that the user can read the query.
  • cache-query-text: This is used for XML parser and the user is not allowed to make any change in it.
    		•
    Cache-policy When mode is selected as Caching, only those query results will be cached for which caching is enabled. The user can also specify caching policies for all queries.
  • vary-by-cache-param: User can specify which parameter should be included as part of cache key. NCache Entity Framework Caching provider will replace the actual parameter in config file with its own name which should follow the following parameter format: @param_[parameter-no/index].
    A sample query with parameters:
    "SELECT * FROM dbo.customers WHERE customer_id = @param_0 and dob > @param_1;"
  • enable: Determines whether caching is enabled for this query or not. The default value is True.
  • expiration-type: Type of expiration, it can be 'Absolute' or 'Sliding'. Default value is Sliding.
  • expiration-time: Expiration time for this query. The default value is 180 sec (3 min).
  • dbsyncdependency: Determines whether to enable Database Dependency for this query or not.The default value is False.
  • resyncProviderName: Determines whether to enable resync option for a query or not.
    		•
    Important

    SQL Dependency will be registered only for those SQL queries that satisfy all the conditions for SQL Notification Registration as described in the Microsoft documentation.

    Warning

    InProc Client Cache stores items in object form, therefore if object is modified by the application, it should be updated back to the cache so that other remote clustered cache and other Client Caches have no data integrity issue.

    See Also

    Using NCache as Entity Framework Second Level Cache
    NHibernate
    Entity Framework Core Caching