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Benoit_Desclos_'s avatar
Benoit_Desclos_
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May 31, 2017

LTM profile RAMCACHE

Hi,

 

LTM Profile RAMCACHE has only 40 records, but http acceleration profile has 10,000 maximum entries why big-ip limits to 40 records? (ramcache has freespace)

 

2 Replies

  • Hi,

     

    Web Acceleration profiles has multiple options in order to add entries in the BIG-IP cache.

     

    Please review the options below in order to check why your cache has only 40 records:

     

    • Cache Size megabytes
    • Maximum Entries
    • Maximum Age seconds
    • Minimum Object Size bytes
    • Maximum Object Size bytes
    • URI Caching
    • URI List
    • URI:
    • Pin List
    • Include List
    • Exclude List
    • Include Override List
    • Ignore Headers
    • Insert Age Header
    • Aging Rate
  • Hi,

     

    For example, if your objects exceed 10 MB there's no more room for any other object in the cache (If your cache size config has a 10 MB value). Also, if your objects are not betweeen the Minimum/Maximun Object Size (in bytes), the web acceleration profile don't cache/storage those objects in RAM.

     

    The same thing occurs for the other configuration parameters. So check carefully if your objects meet your Web Acceleration profile "matching" criteria.

     

    You could use the command tmsh show ltm profile ramcache in order to check the cache Miss/Hit process.

     

    Here you have some details:

     

    Cacheable content

     

    You can configure the BIG-IP cache feature to cache the following content types:

     

    • 200, 203, 300, 301, and 410 HTTP responses
    • Responses to HTTP GET requests
    • Other HTTP methods for URIs specified for inclusion in cached content, or specified in an iRule
    • Content based on the User-Agent and Accept-Encoding values. The cache feature holds different content for Vary headers.

    Non-cacheable content

     

    The cache feature does not cache the following items:

     

    • Data specified by the following Cache-Control headers: private, no-store, no-cache
    • Action-oriented HTTP methods such as HEAD, PUT, DELETE, TRACE, and CONNECT

    More information:

     

    Understanding RAM Caching

     

    K14903: Overview of the Web Acceleration profile (11.x)

     

    :-)