In most storage systems, the storage nodes store data on a local filesystem. Thus, unless they have a dedicated caching layer, they benefit from the usual filesystem cache in the host’s free memory. However, in erasure-coded storage systems, caching is effective only if all the systematic fragments corresponding to an object are in the cache. In this work, we propose a new caching policy adapting traditional methods to erasure-coded storage systems. The main idea of our solution is to cache a full object rather than fragments object. A simulation-based evaluation showed that our full replica solution is able to improve the cache hit ratio and reduce the cache waste ratio compared to the traditional caching method. Moreover, experimental evaluation has been conducted. It indicates that our implementation not only validates the previous results but also shows that cache hits on full replicas have a better request response time.

在大多数存储系统中，存储节点将数据存储在本地文件系统上。因此，除非它们有专用的缓存层，否则它们会受益于主机空闲内存中通常的文件系统缓存。然而，在纠删码存储系统中，只有当一个对象对应的所有系统片段都在缓存中时，缓存才有效。在这项工作中，我们提出了一种新的缓存策略，将传统方法应用于纠删码存储系统。我们解决方案的主要思想是缓存一个完整的对象而不是片段对象。基于模拟的评估表明，与传统缓存方法相比，我们的完整副本解决方案能够提高缓存命中率并减少缓存浪费率。此外，还进行了实验评估。