摘要:
Techniques for efficiently authenticating multiple objects and clustering objects based on access patterns are provided. For example, in an illustrative aspect of the invention, a technique for generating and/or reading authentication information, wherein the authentication information provides evidence that a plurality of objects were one of generated and sent by an entity, comprises using one or more object access patterns indicative of whether at least two of the plurality of objects are accessed within a similar time period to group objects together to reduce an overhead for at least one of generating and reading the authentication information.
摘要:
Automated techniques are disclosed for minimizing communication between nodes in a system comprising multiple nodes for executing requests in which a request type is associated with a particular node. For example, a technique comprises the following steps. Information is maintained about frequencies of compound requests received and individual requests comprising the compound requests. For a plurality of request types which frequently occur in a compound request, the plurality of request types is associated to a same node.As another example, a technique for minimizing communication between nodes, in a system comprising multiple nodes for executing a plurality of applications, comprises the steps of maintaining information about an amount of communication between said applications, and using said information to place said applications on said nodes to minimize communication among said nodes.
摘要:
Techniques are disclosed for managing storage of objects of sizes smaller than a storage transfer unit in a computer system. A plurality of storage transfer units are maintained in a first storage medium (e.g., disk storage) organized by a quantity of free space in a storage transfer unit. A cache is maintained in a second storage medium (e.g., main memory), the cache including a copy of at least one of the plurality of storage transfer units. In response to a request to store an object of a size less than a storage transfer unit, the technique searches for a cached storage transfer unit with sufficient free space to store the object. If no such cached storage transfer unit can be found, the technique identifies an uncached storage transfer unit with sufficient free space to store the object and stores a copy of the identified storage transfer unit in the cache. The object is stored in the identified storage transfer unit by modifying at least one data structure in the cache and subsequently writing a cached copy of the storage transfer unit to the first storage medium.
摘要:
Techniques for cache management including cache replacement are provided. In one aspect, a distributed caching technique of the invention comprises the use of a central cache and one or more local caches. The central cache communicates with the one or more local caches and coordinates updates to the local caches, including cache replacement. The invention also provides techniques for adaptively determining holding times associated with data storage applications such as those involving caches.
摘要:
Techniques for efficiently authenticating multiple objects and clustering objects based on access patterns are provided. For example, in an illustrative aspect of the invention, a technique for generating and/or reading authentication information, wherein the authentication information provides evidence that a plurality of objects were one of generated and sent by an entity, comprises using one or more object access patterns indicative of whether at least two of the plurality of objects are accessed within a similar time period to group objects together to reduce an overhead for at least one of generating and reading the authentication information.
摘要:
Improved key management techniques are disclosed for temporal access control of one or more services in a computer network. For example, a method for providing access control in a client-server system includes the following steps. A client obtains an authorization key for a time interval. A server derives an encryption key corresponding to a given time and uses the encryption key to encrypt a message. The client derives a decryption key corresponding to the given time and decrypts the message.
摘要:
A system and method for maintaining consistency in a system where multiple copies of an object may exist is provided for maintaining consistent copies. Consistency is maintained using a plurality of consistency policies in which at least one consistency policy results in different performance than a second consistency policy. A consistency policy is selected from the plurality consistency policies for each object to improve system performance.
摘要:
A method and apparatus in a data processing system for caching data in an internal cache and in an external cache. A set of fragments is received for caching. A location is identified to store each fragment within the plurality of fragments based on a rate of change of data in each fragment. The set of fragments is stored in the internal cache and the external cache using the location identified for each fragment within the plurality of fragments.
摘要:
Objects are cached in a system adapted to receive requests for said objects from one or more clients. The system has at least one of a plurality of nodes. Each node of the plurality of nodes includes at least one of a plurality of caches. One or more performance criteria of the system are selected. At least one of a plurality of metrics is assigned to a selected performance criterion. The desirability of storing an object of the objects in any one of the plurality of caches is calculated by assigning at least one of a plurality of desirability values to at least one of the objects based on the at least one of the plurality metrics. Any one of the objects stored in the at least one of the plurality of caches is replaced based on the at least one of the plurality of desirability values.
摘要:
Techniques for maintaining consistent replicas of data are disclosed. By way of example, a method for managing copies of objects within caches, in a system including multiple caches, includes the following steps. Consistent copies of objects are maintained within the caches. A home cache for each object is maintained, wherein the home cache maintains information identifying other caches likely containing a copy of the object. In response to a request to update an object, the home cache for the object is contacted to identify other caches which might have copies of the object.