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Memcached中的多个缓存

[英]Multiple caches in Memcached

原文 2012-06-07 15:44:56 2 1 java/ caching/ memcached

I am migrating caches from EhCache to Memcached . 我正在将缓存从EhCache迁移到Memcached 。 With only 1 Memcached instance, is there a way to have multiple caches (as in EhCache)? 只有一个Memcached实例，有没有办法拥有多个缓存（如在EhCache中）？

For example, I want to have a "Users" cache, a "Products" cache, etc... The main reason for that is to be able to monitor and configure each cache separately, and be able to clear them separately too. 例如，我想要一个“用户”缓存，一个“产品”缓存等......主要原因是能够分别监视和配置每个缓存，并且能够单独清除它们。

1 个解决方案

Typically, this sort of behavior is achieved in memcached via namespacing. 通常，这种行为是通过命名空间在memcached中实现的。 Within a single memcached instance, one maintains multiple namespaces, each of which represents a different cache. 在单个memcached实例中，一个维护多个名称空间，每个名称空间代表不同的缓存。 However, memcached doesn't natively support namespaces - instead, memcached namespaces are emulated by prefixing keys with a namespace identifier (eg, memcachedClient.get('products.top10') ). 但是，memcached本身不支持命名空间 - 相反，memcached命名空间通过为命名空间标识符添加前缀（例如， memcachedClient.get('products.top10') ）来模拟。 Some memcached clients, like the Python GAE memcached client , abstract this behavior for you. 一些memcached客户端，如Python GAE memcached客户端，为您抽象出这种行为。 However, xmemcached does not, as far as I can tell. 但是，据我所知，xmemcached没有。

You are left with two options. 你有两种选择。

Manually prefix each key you work with. 手动为您使用的每个密钥添加前缀。
Write a thin wrapper around XMemcachedClient with two changes: it has a String namespace member that serves as the prefix value, and it overrides get0() to apply that prefix. 使用两个更改在XMemcachedClient周围写一个瘦包装器：它有一个String namespace成员作为前缀值，它覆盖get0()以应用该前缀。 This is a bit dangerous as it relies on the current XMemcached implementation. 这有点危险，因为它依赖于当前的XMemcached实现。