| --- |
| title: The Inline Cache |
| --- |
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| |
| An inline cache holds region entries for a client application. |
| |
| ## Description of an Inline Cache |
| |
| A cache is formed from a region within a <%=vars.product_name%> cluster, |
| and the cache sits between the client application and a |
| backing data store. |
| |
| <img src="../images/inline-cache.png" id="inline-cache-png" class="image" /> |
| |
| The client application's cache lookup is a region get |
| operation, and a cache write is a region put operation. |
| |
| When the cache (region) has the requested region entry, |
| it quickly responds with the value for a lookup operation. |
| This is a cache hit. |
| If the requested region entry is not in the region, |
| it is a cache miss, |
| and code that has been deployed to the server acquires the |
| entry from the data store. |
| The acquired region entry is written to the region |
| such that future lookups will cause a cache hit. |
| |
| ## Implementation and Configuration |
