What is name caches in distributed systems..?
Answers
Name services facilitate sharing in distributed environments by allowing objects to be
named unambiguously and maintaining a set of application-defined attributes for each named
object. Existing distributed name services, which manage names based on their syntactic
structure, may lack the flexibility needed by large, diverse, and evolving computing communities. A new approach, structure-free name management, separates three activities:
choosing names, selecting the storage sites for object attributes, and resolving an object's
name to its attributes. Administrative entities apportion the responsibility for managing
various names, while the name service's information needed to locate an object's attributes
can be independently reconfigured to improve performance or meet changing demands.
An analytical performance model for distributed name services provides assessments of
the effect of various design and configuration choices on the cost of name service operations.
Measurements of Xerox's Grapevine registration service are used as inputs to the model
to demonstrate the benefits of replicating an object's attributes to coincide with sizeable
localities of interest. Additional performance benefits result from clients' acquiring local
caches of name service data treated as hints. A cache management strategy that maintains
a minimum level of cache accuracy is shown to be more effective than the usual technique
of maximizing the hit ratio; cache managers can guarantee reduced overall response times,
even though clients must occasionally recover from outdated cache data.