--- title: Caching for Knowledge base articles Genius Results description: AI Search provides two query-time caches to improve search performance for Knowledge base articles Genius Results. Caching enables AI Search to return previously generated answers without submitting knowledge articles to the Now LLM Service for answer generation.Improve performance for Knowledge base articles Genius Results by pinning frequently used answers in the second-level cache. Pinning an answer exempts it from the cache's purge mechanism. locale: en-US canonical_url: https://www.servicenow.com/docs/r/australia/platform-administration/ai-search/caching-now-assist-q-a-gr.html release: australia product: AI Search classification: ai-search topic_type: concept last_updated: "2026-07-25" reading_time_minutes: 9 keywords: [ServiceNow Otto, AI Agents, generative AI, agentic AI, ServiceNow Otto, AI Agents, generative AI, agentic AI] breadcrumb: [Knowledge base articles Genius Results, Configuring ServiceNow Otto for AI Search, ServiceNow Otto for AI Search, ServiceNow Store applications and integrations, AI Search, Search administration, Configure core features, Administer the ServiceNow AI Platform] --- # Caching for Knowledge base articles Genius Results AI Search provides two query-time caches to improve search performance for Knowledge base articles Genius Results. Caching enables AI Search to return previously generated answers without submitting knowledge articles to the Now LLM Service for answer generation. ## Knowledge base articles Genius Results caching overview When a search query triggers a Knowledge base articles Genius Result configuration, AI Search uses the search query and the sys\_id of the search's top-ranked knowledge article search result to look for cached article summaries. If no article summary is found in the active caches, AI Search submits the search query and article sys\_id to the Now LLM Service for answer generation. **Note:** By default, AI Search only uses the first-level cache and the Now LLM Service when finding Knowledge base articles Genius Result answers. To enable the second-level cache or disable use of the Now LLM Service, administrators can change the operational mode for the caches as described in this topic. The query-time caches only support English-language searches, knowledge articles, and answers. ## Cache levels The cache includes two levels which work in different ways to improve search performance for Knowledge base articles Genius Results. - **First-level cache** The first-level cache comprises a list of key-value pairs stored in memory for fast access. Each cache entry has a key that includes a search query and the sys\_id of a knowledge article returned by that query. The cache entry's value includes the summary generated by the Now LLM Service for the specified search query and knowledge article. When checking the first-level cache, AI Search compares your search query and the sys\_id of your knowledge article search result to the cache entry keys. If it finds a matching key, it returns the article summary from the corresponding cache entry value. Otherwise, it goes on to check the second-level cache. **Note:** The first-level cache only yields a result when your search query is an exact keyword match for the cached search query. For example, if you search for `avoiding scams` you won't get a result for a cached entry with search query `how to prevent scams` because the two search queries don't contain the same terms. - **Second-level cache** The second-level cache comprises a table that is configured as an AI Search indexed source. Each record on this table is a cache entry, and includes a search query, the sys\_id for an associated knowledge article search result, the summary generated for that query and knowledge article, and other fields such as pinned, sys\_updated\_on, and run\_as. AI Search updates the index for this table whenever its records are created, updated, or deleted. This index update operation can take up to a minute. When checking the second-level cache, AI Search queries the indexed table, looking for an entry that matches your search query and the sys\_id of your knowledge article search result. If it finds a matching entry, it returns the article summary stored in the indexed table. Otherwise, it goes on to submit your search query and knowledge article search result to the Now LLM Service. **Note:** Unlike the first-level cache, the second-level cache compares search query meanings using semantic vector search, so you may get a cache result even if your search query isn't an exact keyword match for the cached search query. For example, if you search for `avoiding scams` you might get the result for a cached entry with search query `how to prevent scams` because the meanings of the two search queries are similar. For more information on semantic vector search, see [Semantic vector search in AI Search](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/australia/markdown/australia/platform-administration/ai-search/semantic-search-ais.md). ## Benefits of caching Caching for Knowledge base articles Genius Results provides the following benefits: - Decreases average response time for common Knowledge base articles Genius Result answers - Lowers Now Assist entitlement consumption by reducing the number of search query results sent to the Now LLM Service for Knowledge base articles answer extraction - Increases the likelihood of returning a Knowledge base articles Genius Result answer - Improves search consistency by returning the same Knowledge base articles Genius Result answer for similar searches ## Content Security for cached queries Because AI Search applies Content Security restrictions to your search before it matches knowledge articles and checks the caches, neither cache returns hits for knowledge articles that you don't have access to. For full details on AI Search's Content Security model, see [Content security in AI Search](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/australia/markdown/australia/platform-administration/ai-search/content-security-ais.md). ## Cache modes The Knowledge base articles Genius Result answer caches support the following operational modes: - **off**: Use the first-level cache and the Now LLM Service to find Knowledge base articles Genius Result answers. AI Search looks in the first-level cache for Knowledge base articles Genius Result answers that exactly match your search query and knowledge article result. If it doesn't find a matching answer, it sends your query and Knowledge article sys\_id to the Now LLM Service for answer generation. Knowledge base articles Genius Result answers generated by the Now LLM Service populate the first-level cache. When using Dynamic Translation, AI Search bypasses the caches and queries the Now LLM Service to generate an answer for the Knowledge base articles Genius Result. - **offline**: Use the first-level and second-level caches to find Knowledge base articles Genius Result answers. Don't submit queries to the Now LLM Service. AI Search looks in the first-level cache for Knowledge base articles Genius Result answers that exactly match your search query and knowledge article result. If it doesn't find a matching answer, it uses semantic vector search to look for answers that match the meaning of your query in the second-level cache. If no cached answers match your query and knowledge article result, AI Search returns no answer for the Knowledge base articles Genius Result. Knowledge base articles Genius Result answers found in the second-level cache populate the first-level cache. When using Dynamic Translation, AI Search bypasses the caches and returns no answer for the Knowledge base articles Genius Result. - **online**: Use the first-level and second-level caches and the Now LLM Service to find Knowledge base articles Genius Result answers. AI Search looks in the first-level cache for Knowledge base articles Genius Result answers that exactly match your search query and knowledge article result. If it doesn't find a matching answer, it uses semantic vector search to look for answers that match the meaning of your query in the second-level cache. If no cached answers match your query and knowledge article result, AI Search submits the query and article sys\_id to the Now LLM Service for answer generation. Knowledge base articles Genius Result answers generated by the Now LLM Service populate the first-level and second-level caches. When using Dynamic Translation, AI Search bypasses the caches and queries the Now LLM Service to generate an answer for the Knowledge base articles Genius Result. The default operational mode is **off**. Administrators can change the operational mode for the Knowledge base articles Genius Result answer caches by setting the value for the **sn\_ais\_assist.semantic\_cache\_mode** system property to **off**, **offline**, or **online**. For details on system property settings, see [Add a system property](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/australia/markdown/australia/platform-administration/t_AddAPropertyUsingSysPropsList.md). For more details on using Dynamic Translation with ServiceNow Otto for AI Search Genius Results, see [Dynamic Translation for Knowledge base articles Genius Results](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/australia/markdown/australia/platform-administration/ai-search/dynamic-translation-na-gr.md). ## Scheduled job for cache management The **Update Semantic Cache** scheduled job runs daily to perform the following tasks: - Populate the second-level cache with results for the most frequently submitted queries found in the Search Event \[sys\_search\_event\] search signal table. For more information on this table, see [Search signal tables](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/australia/markdown/australia/platform-administration/search-administration/search-signal-tables.md). - Purge all unpinned second-level cache entries that haven't been used in the past seven days. Search administrators can pin results in the second-level cache table to prevent them from being purged. For more details on this procedure, see [Pin cached answers for Knowledge base articles Genius Results](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/australia/markdown/australia/platform-administration/ai-search/caching-now-assist-q-a-gr.md). **Parent Topic:**[Knowledge base articles Genius Results](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/australia/markdown/australia/platform-administration/ai-search/now-assist-qna-genius-results.md) ## Pin cached answers for Knowledge base articles Genius Results Improve performance for Knowledge base articles Genius Results by pinning frequently used answers in the second-level cache. Pinning an answer exempts it from the cache's purge mechanism. ### Before you begin The ServiceNow Otto for AI Search ServiceNow® Store application must be installed on your instance. For details on installing this application, see [Install ServiceNow Otto for AI Search](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/australia/markdown/australia/platform-administration/ai-search/install-now-assist-ais.md). Role required: ais\_admin ### About this task Search administrators can pin entries in the second-level cache for Knowledge base articles Genius Result answers. The **Update Semantic Cache** scheduled job ignores pinned entries when purging the second-level cache. Pinning frequently used entries helps improve search performance by enabling AI Search to return previously generated Knowledge base articles Genius Result answers without submitting knowledge articles to the Now LLM Service for answer generation. To learn more about the second-level Knowledge base articles Genius Result answer cache and its usage, see [Caching for Knowledge base articles Genius Results](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/australia/markdown/australia/platform-administration/ai-search/caching-now-assist-q-a-gr.md). ### Procedure 1. Navigate to the ServiceNow Otto for AI Search Semantic Cache \[sn\_ais\_assist\_semantic\_cache\] table's list view. 1. Select **All**. 2. In the **Filter** field, enter `sn_ais_assist_semantic_cache.list`. 3. Press **Enter**. Each record in this table represents a second-level cache entry. The table is populated with Knowledge base articles Genius Result answers previously generated by the Now LLM Service. 2. Update each cache entry record that you want to pin. 1. Open the cache entry record by selecting it from the list view. 2. Set the value of the record's **Pinned** field to **true**. 3. Select **Update**. ### Result The **Update Semantic Cache** scheduled job ignores your pinned entries when purging the second-level cache.