Efficient File Access In A Large Repository Using A Two-Level Cache

A computer-executed method comprising:

• maintaining a shared cache comprising a hierarchy of hash tables, each hash table of the hierarchy of hash tables storing information for child resources of a container resource in a hierarchy of resources;
• identifying information for a target resource of a particular path expression by determining whether information for resources corresponding to segments of the particular path expression are represented in the hierarchy of hash tables;
• and
• in response to determining that a new cache entry should be added to the shared cache, performing the steps of:
• evicting one or more hash table entries, from the shared cache, based on the positions of the one or more hash table entries in the hierarchy of hash tables relative to other hash table entries in the hierarchy of hash tables;
• adding the new cache entry to the shared cache;
• wherein the method is performed by one or more computing devices.

A non-transitory computer readable medium that stores instructions which, when executed by one or more processors, cause one or more computing devices to perform the steps of:

• maintaining a hierarchy of hash tables, each hash table of the hierarchy of hash tables storing resource identifiers for a set of child resources of a container resource in a hierarchy of resources;
• wherein a particular entry of a first hash table of the hierarchy of hash tables includes a resource identifier for a particular child resource of a particular container resource in the hierarchy of resources;
• and
• removing the particular entry from the first hash table based on a characteristic of a resource associated with the particular entry.

A non-transitory computer readable medium that stores instructions which, when executed by one or more processors, cause one or more computing devices to perform the steps of:

• maintaining a shared cache comprising a hierarchy of hash tables, each hash table of the hierarchy of hash tables storing information for child resources of a container resource in a hierarchy of resources;
• identifying information for a target resource of a particular path expression by determining whether information for resources corresponding to segments of the particular path expression are represented in the hierarchy of hash tables;
• and
• in response to determining that a new cache entry should be added to the shared cache, performing the steps of:
• evicting one or more hash table entries, from the shared cache, based on the positions of the one or more hash table entries in the hierarchy of hash tables relative to other hash table entries in the hierarchy of hash tables;
• adding the new cache entry to the shared cache.