Many caches are used in Knowledge Management in order to ensure that the system performs well. It is important that you configure the caches correctly after they have been created.
This section lists the technical components of Knowledge Management that use caches. As well as a short explanation of the caches, this section also includes a recommendation for configuration in a standard scenario.
Components other than caches also influence performance. The processor performance and main memory structure of the portal server, the available bandwidth, user figures, and the number of documents managed all influence the performance of the portal.
The configuration of a cache used in Content Management comprises various parameters (see Caches ). The optimal values for these attributes depend on the following factors:
The caches listed below are memory caches that are stored in the main memory of the portal server.
ACL Security Manager
The ACL security manager uses a cache in which access control lists (ACLs) that are valid for resources are stored. Since ACLs are inherited, it is possible for there to be an entry in the cache for every resource of the underlying repository. ACLs are cache entries that need little memory space (only a few KB). The ACL security manager is used constantly, so the cache should be large.
ca_rsrc_acl (Effective ACL Cache)
Parameter | Setting | Additional Comments |
---|---|---|
Restart Lifetime on Access |
Not activated |
|
Singleton |
Activated |
More than one ACL security managers can use a cache. |
Assumed Entry Size |
0 |
This value is not used if the maximum size of a cache is set to unlimited (Maximum Cache Size = 0). |
Capacity |
This value depends on the number of frequently used resources within the repositories that are assigned to the ACL security manager. |
|
Default Time-to-Live |
Between half an hour and several hours |
The cache is checked for expired entries within a CM installation, so this value cannot be too high. |
Maximum Cache Size |
0 (unlimited) |
The actual size of the ACLs is not defined. |
Maximum Entry Size |
0 (unlimited) |
|
You select the cache ca_rsrc_aclin the configuration of repository managers under Content Management →Repository Managersin the parameter ACL Manager Cache.
(JDBC) ACL Manager
The (JDBC) ACL manager uses two caches. One of the caches is for ACLs; the other for permissions and object types. The ACL cache contains entries for every ACL that is used by the system. The cache for permissions contains only a few entries. The entries are mainly static.
ACLs are cache entries that need only a little memory space (only a few KB). Permissions and object types need very little memory space (less than 1KB). The ACL manager is used constantly, so the cache should be large.
ca_cm_rep_acl, ca_cm_srv_acl (ACL Cache)
Parameter | Setting | Additional Comments |
---|---|---|
Restart Lifetime on Access |
Not activated |
|
Singleton |
Activated |
More than one ACL manager can use a cache. |
Assumed Entry Size |
0 |
This value is not used if the maximum size of a cache is set to unlimited (Maximum Cache Size = 0). |
Capacity |
This value depends on the number of frequently used resources with ACLs within the repositories that are assigned to the ACL manager. |
|
Default Time-to-Live |
Between half an hour and several hours |
The cache is checked for expired entries within a CM installation, so this value cannot be too high. |
Maximum Cache Size |
0 (unlimited) |
The actual size of the ACLs is not defined. |
Maximum Entry Size |
0 (unlimited) |
|
You select the caches ca_cm_rep_acl and ca_cm_srv_acl in the configuration of the ACL manager under Content Management → Utilities →ACL Managersin the parameter ACL Cache .
ca_cm_rep_acl_perm, ca_cm_srv_acl_perm (Cache for Permissions)
Parameter | Setting | Additional Comments |
---|---|---|
Restart Lifetime on Access |
Not activated |
|
Singleton |
Activated |
More than one ACL manager can use a cache. |
Assumed Entry Size |
0 |
This value is not used if the maximum size of a cache is set to unlimited (Maximum Cache Size = 0). |
Capacity |
100 |
|
Default Time-to-Live |
Between half an hour and several hours |
The cache is checked for expired entries within a CM installation, so this value cannot be too high. |
Maximum Cache Size |
0 (unlimited) |
|
Maximum Entry Size |
0 (unlimited) |
|
You select the caches ca_cm_rep_acl_perm and ca_cm_srv_acl_perm in the configuration of the ACL manager under Content Management → Utilities →ACL Managersin the parameter Permission Cache.
Application-Defined Properties
The application property service uses two caches to store the properties of resources. One cache is for storing user-dependent properties. The second cache is used to store user-independent properties. Entries can be medium-sized or small depending on the number of properties and their content.
ca_props_1, ca_props_2 (Caches for Application-Defined Properties)
Parameter | Setting | Additional Comments |
---|---|---|
Restart Lifetime on Access |
Not activated |
|
Singleton |
Activated |
|
Assumed Entry Size |
0 |
This value is not used if the maximum size of a cache is set to unlimited (Maximum Cache Size = 0). |
Capacity |
This value depends on the number of frequently used resources with application-defined properties within the repositories that are assigned to the application property service. |
|
Default Time-to-Live |
Between half an hour and several hours |
The cache is checked for expired entries within a CM installation, so this value cannot be too high. |
Maximum Cache Size |
0 (unlimited) |
The actual size is not defined. |
Maximum Entry Size |
0 (unlimited) |
|
The caches ca_props_1 and ca_props_2 for the application property service are already selected under Content Management → Repository Services → Application Properties Service.
URL Access For Content
The utility URL access for content uses its cache to store the content of external link resources. These entries may need a large amount of memory space.
ca_contentaccess (Cache for URL Access for Content)
Parameter | Setting | Additional Comments |
---|---|---|
Restart Lifetime on Access |
Not activated |
|
Singleton |
Activated |
|
Assumed Entry Size |
0 |
This value is not used if the maximum size of a cache is set to unlimited (Maximum Cache Size = 0). |
Capacity |
The value depends on the number of frequently used external-link resources. |
|
Default Time-to-Live |
Between half an hour and several hours |
The cache is checked for expired entries within a CM installation, so this value cannot be too high. |
Maximum Cache Size |
0 (unlimited) |
The actual size of the content is not defined. |
Maximum Entry Size |
0 (unlimited) |
|
The cache ca_contentaccess is already selected under Content Management → Utilities → URLAccess for Content.
CM Repository Manager
A CM repository manager uses two other caches as well as the ACL cache.
CM Cache
This cache stores the names of resources, and properties and locks.No content is stored in the cache.
ca_cm (CM Cache)
Parameter | Setting | Additional Comments |
---|---|---|
Restart Lifetime on Access |
Not activated |
|
Singleton |
Activated |
|
Assumed Entry Size |
0 |
This value is not used if the maximum entry size is set to unlimited (Maximum Entry Size = 0). |
Capacity |
This value depends on the number of frequently used resources within the repository. |
|
Default Time-to-Live |
Between half an hour and several hours |
The cache is checked for expired entries within a CM installation, so this value cannot be too high. |
Maximum Cache Size |
0 (unlimited) |
The actual size of the mappings is not defined. |
Maximum Entry Size |
0 (unlimited) |
|
You can normally select the cache ca_cm under Content Management → Repository Managers → CM Repository.
Cache for Small Content
This cache is used by a CM repository manager for content smaller than 32 KB.
ca_cm_content (Cache for Small Content)
Parameter | Setting | Additional Comments |
---|---|---|
Restart Lifetime on Access |
Not activated |
|
Singleton |
Not activated |
|
Assumed Entry Size |
0 |
This value is not used if the maximum entry size is set to unlimited (Maximum Entry Size = 0). |
Capacity |
This value depends on the number of frequently used resources within the repository. |
|
Default Time-to-Live |
Between half an hour and several hours |
The cache is checked for expired entries within a CM installation, so this value cannot be too high. |
Maximum Cache Size |
0 (unlimited) |
The actual size of the mappings is not defined. |
Maximum Entry Size |
0 (unlimited) |
|
You can normally select the cache ca_cm_content under Content Management → Repository Managers → CM Repository.
Web Repository Manager
The content of resources (Web sites) is stored in the cache of a Web repository manager . The entries can be medium-sized or large, but are usually small and need little memory space (10 - 20 KB).
Web repository cache
Parameter | Setting | Additional Comments |
---|---|---|
Restart Lifetime on Access |
Not activated |
|
Singleton |
Activated |
More than one Web repository can use a cache. |
Assumed Entry Size |
10 KB |
|
Capacity |
This value depends on the number of frequently used resources within the repository. |
|
Default Time-to-Live |
1-2 hours |
|
Maximum Cache Size |
This value depends on the amount of memory space required by the cache. |
|
Maximum Entry Size |
10 KB |
|
You should create a separate cache for each Web repository. You then select the cache in the configuration of the Web repository manager under Content Management → Repository Managers → Web Repository.
WebDAV Repository Manager
Resources are stored in the cache of a WebDAV repository manager . The cache entries need little memory space.
WebDAV repository cache
Parameter | Setting | Additional Comments |
---|---|---|
Restart Lifetime on Access |
Not activated |
|
Singleton |
Activated |
|
Assumed Entry Size |
0 |
This value is not used if the maximum size of a cache is set to unlimited (Maximum Cache Size = 0). |
Capacity |
This value depends on the number of frequently used resources within the repository. |
|
Default Time-to-Live |
This value depends on the usage of the connected WebDAV server. Choose a few minutes if changes are often made by other clients. |
|
Maximum Cache Size |
0 (unlimited) |
The actual size of the mappings is not defined. |
Maximum Entry Size |
0 (unlimited) |
|
You should create a separate cache for each WebDAV repository. You then select the cache in the configuration of the WebDAV repository manager under Content Management → Repository Managers → WebDAV Repository.
Navigation Point Cache
This cache contains navigation points of the flexible user interface. The entries in the cache are user-specific. A cache entry for storing user-specific navigation points is created for every user. If the entries in the cache become obsolete, for example, because of a timeout, the user interface no longer displays the old navigation points.
nm (Navigation Point Cache)
Parameter | Setting |
---|---|
Restart Lifetime on Access |
Activated |
Singleton |
Activated |
Assumed Entry Size |
0 |
Capacity |
5000 |
Default Time-to-Live |
Half an hour (1800 seconds) |
Maximum Cache Size |
0 (unlimited) |
Maximum Entry Size |
0 (unlimited) |
The cache nm is used internally by the system. It does not need to be specified in the configuration of other components.
Object Type Handler Cache
This cache is used by the object type handler service . It stores the URIs of resources that have object type definition files and whose object type definition files have already been found.
oth (Object Type Handler Cache)
Parameter | Setting | Additional Comments |
---|---|---|
Restart Lifetime on Access |
Activated |
Prevents entries from being deleted from the cache whilst they are still being used. |
Singleton |
Activated |
|
Assumed Entry Size |
0 |
This value is not used if the maximum size of a cache is set to unlimited (Maximum Cache Size = 0). |
Capacity |
This value depends on the number of frequently used resource URIs within the entire CM. |
|
Default Time-to-Live |
Half an hour (1800 seconds) |
The cache is checked for expired entries within a CM installation, so this value cannot be too high. |
Maximum Cache Size |
0 (unlimited) |
The actual size of the mappings is not defined. |
Maximum Entry Size |
0 (unlimited) |
|
The cache oth is already selected under Content Management → Global Services → Object Type Handler Service.
Rendering Cache
This cache is used by the KM user interface (see Debugging Settings ). Various interface-related objects and settings are stored temporarily in it.
rendering (Rendering Cache)
Parameter | Setting | Additional Comments |
---|---|---|
Restart Lifetime on Access |
Activated |
Prevents entries from being deleted from the cache whilst they are still being used. |
Singleton |
Activated |
|
Assumed Entry Size |
0 |
This value is not used if the maximum size of a cache is set to unlimited (Maximum Cache Size = 0). |
Capacity |
5000 |
|
Default Time-to-Live |
Half an hour (1800 seconds) |
The cache is checked for expired entries within a CM installation, so this value cannot be too high. |
Maximum Cache Size |
0 (unlimited) |
The actual size of the mappings is not defined. |
Maximum Entry Size |
0 (unlimited) |
|
The cache rendering is already selected under Content Management → User Interface → Debugging Settings.
Control Status Service Cache
The control status serviceallows rendering components (for example, controls) to persistently store structured data using HTTP request cycles and to access it. This data is stored temporarily in the corresponding cache.
css (Status Cache)
Parameter | Setting | Additional Comments |
---|---|---|
Restart Lifetime on Access |
Activated |
Prevents entries from being deleted from the cache whilst they are still being used. |
Singleton |
Activated |
|
Assumed Entry Size |
0 |
This value is not used if the maximum size of a cache is set to unlimited (Maximum Cache Size = 0). |
Capacity |
The capacity should be three times as large as the number of users who work simultaneously within a 10-minute timeframe on a portal node. |
Increase this value if you receive error messages (for example, Cache Expired) when working with iViews (this includes navigating, sorting, and copying objects) that are based on the flexible user interface. However, you should note that a too high capacity can lead to out-of-memory errors. |
Default Time-to-Live |
Half an hour (1800 seconds) |
The cache is checked for expired entries within a CM installation, so this value cannot be too high. |
Maximum Cache Size |
0 (unlimited) |
The actual size of the mappings is not defined. |
Maximum Entry Size |
0 (unlimited) |
|
The cache css is already configured and is used internally by the system.
XSLT Pipeline Processor Cache
The XSLT pipeline processor uses this cache to store temporarily data structures that are used for XML transformations (see Pipeline Add-Ons ).
ca_pipeline (XSLT Pipeline Processor Cache)
Parameter | Setting |
---|---|
Restart Lifetime on Access |
Not activated |
Singleton |
Activated |
Assumed Entry Size |
0 |
Capacity |
50 |
Default Time-to-Live |
0 |
Maximum Cache Size |
0 (unlimited) |
Maximum Entry Size |
0 (unlimited) |
The cache ca_pipeline is already selected under Content Management → Global Services → Pipeline Add-Ons → XSLT Pipeline Processor.
Cache for XML Forms List Entries
This cache temporarily stores list entries that are used in the preview of news items, for example, in the news browser. A list entry corresponds to an element in the cache.
ca_xmlforms_renderlistitems (Cache for XML Forms List Entries)
Parameter | Setting | Additional Comments |
---|---|---|
Restart Lifetime on Access |
Not activated |
|
Singleton |
Activated |
|
Assumed Entry Size |
0 |
This value is not used if the maximum size of a cache is set to unlimited (Maximum Cache Size = 0). |
Capacity |
100 |
Raise this value if you use a large number of news items in your scenario and want to display them in list entries as a preview. |
Default Time-to-Live |
0 (unlimited) |
|
Maximum Cache Size |
0 (unlimited) |
The actual size of the mappings is not defined. |
Maximum Entry Size |
300000 |
|
The cache ca_xmlforms_renderlistitems is used internally by the system. It does not need to be specified in the configuration of other components.
Classification Cache
This cache stores temporary application data of the classification inbox and taxonomy query builder. This data is needed for the reconstruction of the user interface (see Classification Inbox and Taxonomy Query Builder ).
classification (Classification Cache)
Parameter | Setting | Additional Comments |
---|---|---|
Restart Lifetime on Access |
Activated |
|
Singleton |
Activated |
|
Assumed Entry Size |
0 |
This value is not used if the maximum size of a cache is set to unlimited (Maximum Cache Size = 0). |
Capacity |
20 |
Raise this value if more than 20 content managers use the classification inbox or taxonomy query builder in your scenario at the same time. |
Default Time-to-Live |
Half an hour (1800 seconds) |
|
Maximum Cache Size |
0 (unlimited) |
The actual size of the mappings is not defined. |
Maximum Entry Size |
0 (unlimited) |
|
The cache classification is used internally by the system. It does not need to be specified in the configuration of other components.
TREX Caches
The component Search and Classification (TREX) uses several caches. For more information, see TREX Caches .
To create a memory cache or to change the configuration of an existing one, launch the KM configuration and choose Content Management → Utilities → Caches → Memory Caches.
You can determine a more precise value for the capacity of a cache by using the cache monitor .
Recommendations for Cache Configuration in a Standard Scenario
The table below contains recommendations for the cache configuration for a normal KM implementation. If you access particular repositories (for example, a Web repository) often, you should modify the listed values accordingly. The cache monitor helps you to do this.
Cache | Technical Name | Restart Lifetime on Access | Singleton | Assumed Entry Size | Capacity | Default Time to Live | Max Cache Size | Max Entry Size |
---|---|---|---|---|---|---|---|---|
Effective ACL cache |
ca _rsrc_acl |
- |
Activated |
0 |
10000 |
1800 |
0 |
0 |
ACL Cache |
ca_cm_rep_acl ca_cm_srv_acl |
- |
Activated |
0 |
10000 |
1800 |
0 |
0 |
Cache for permissions |
ca_cm_rep_acl_perm ca_cm_srv_acl_perm |
- |
Activated |
0 |
100 |
1800 |
0 |
0 |
Cache for application-defined properties |
ca_props_1 ca_props_2 |
- |
Activated |
0 |
10000 |
1800 |
0 |
0 |
Cache for URL access for content |
ca_contentaccess |
- |
Activated |
0 |
500 |
1800 |
0 |
0 |
CM Cache |
ca_cm |
- |
- |
0 |
5000 |
1800 |
0 |
0 |
Cache for small content |
ca_cm_content |
- |
- |
0 |
10000 |
1800 |
0 |
0 |
Web repository cache |
Not normally defined |
- |
Activated |
10000 |
10000 |
7200 |
10000000 |
10000 |
WebDAV repository cache |
Not normally defined |
- |
Activated |
0 |
1000 |
1800 |
0 |
0 |
Navigation point cache |
nm |
Activated |
Activated |
0 |
5000 |
1800 |
0 |
0 |
Object type handler cache |
oth |
Activated |
Activated |
0 |
5000 |
1800 |
0 |
0 |
Rendering cache |
rendering |
Activated |
Activated |
0 |
5000 |
1800 |
0 |
0 |
Control status service cache |
css |
Activated |
Activated |
0 |
500 |
1800 |
0 |
0 |
XSLT pipeline processor cache |
ca_pipeline |
- |
Activated |
0 |
50 |
0 |
0 |
0 |
Cache for XML forms list entries |
ca_xmlforms_ renderlistitems |
- |
Activated |
0 |
100 |
0 |
0 |
300000 |
Classification Cache |
classification |
Activated |
Activated |
0 |
20 |
1800 |
0 |
0 |
TREX administration cache |
trexadmin |
- |
Activated |
0 |
100 |
300 |
0 |
0 |
TREX memory cache |
trexmemory |
- |
Activated |
0 |
100 |
300 |
0 |
0 |