摘要:
The present invention is directed to a system and a method for evaluating a plurality of moving queries over moving objects. The method, which can be embodied in a computer readable medium containing computer readable code, constructs motion-adaptive bounding boxes around the objects and queries and indexes the objects and queries based upon the bounding boxes. Predictive query results are used to optimize the evaluation of the moving queries. The bounding boxes vary in size and shape depending on the speed and motion direction of the objects and queries. The system of the present invention includes the moving objects and queries, each having an associated motion-adaptive bounding box. The system also provides for a monitoring system capable of monitoring the location and motion of the moving objects and moving queries and of evaluating the moving queries. The monitoring system includes a motion-adaptive query index and a motion-adaptive object index.
摘要:
Techniques are disclosed for adaptive source filtering and load shedding in such data stream processing systems. For example, in one aspect of the invention, a method for use in filtering data in a distributed data stream processing system, wherein a server receives and processes one or more data streams from one or more data sources, comprises the steps of the server periodically re-configuring one or more filters and sending the one or more periodically re-configured filters to the one or more data sources, and the one or more data sources performing data filtering based on the one or more periodically re-configured filters received from the server.
摘要:
A plurality of web objects are cached. A first object is within an assigned web partition. A second object is outside of the assigned web partition. The first object is placed in a first amount of space within the cache. A copy of the second object is placed in a second amount of space within the cache. The first amount of space includes and is larger than the second amount of space.
摘要:
Range query techniques are disclosed for use in accordance with data stream processing systems. In one aspect of the invention, a technique is provided for indexing continual range queries for use in data stream processing. For example, a technique for use in processing a data stream comprises obtaining at least one range query to be associated with the data stream, and building a range query index based on the at least one range query using one or more virtual constructs such that the query index is adaptive to one or more changes in a distribution of range query sizes. The step/operation of building the range query index may further comprise building the range query index such that the range query index accommodates one or more changes in query positions outside a monitoring area of the at least one range query. In another aspect of the invention, a technique is provided for incrementally processing continual range queries against moving objects. For example, a technique for evaluating one and more continual range queries over one and more moving objects comprises maintaining a query index with one and more containment-encoded virtual constructs associated with the one and more continual range queries over the one and more moving objects, and incrementally evaluating the one or more continual range queries using the query index.
摘要:
A method and system to map client access patterns in a stateless hypertext server. For each hypertext object access, a plurality of information about the access may be collected, including the requestor address, the hyperlink source, and the hyperlink target. When available, a time stamp of the access and agent information may also be used. The hyperlink source and hyperlink target form a hyperlink access pair, representing a step in the user traversal path on the hypertext objects. These hyperlink access pairs are then mapped into hyperlink access groups. Each hyperlink group represents all the hypertext objects visited by a user along a traversal path. To map hyperlink access pairs into access groups, each access pair is added to an active session if the new access pair can expand the session into a connected traversal path. Once hyperlink groups are identified, user-oriented object usage statistics can be analyzed. When client and/or proxy caching occurs, hypertext objects are fetched locally instead of from the hypertext server. Thus, no requests are made to the server for the cached objects. As a result, it may be required to add valid backward traversal steps to an active session in order to form a valid connected traversal path. One could find any backward traversal path for the needed backward steps. To preserve memory space, a method is also disclosed which finds the shortest valid backward traversal path. Once the client access patterns have been mapped, a user-oriented statistical analysis can be performed.
摘要:
System and method for improving response time of concurrent mergesort operations in an information handling system, which includes one or more logical processors each operating under control of an image of an operating system program, a database storage system for storing data in a predetermined data structure, one or more workfile storage devices for storing workfiles during mergesort operations, means for sorting the data structure into one or more ordered runs, means for determining a logical partition size for the workfile storage devices, means for selecting a least loaded partition, means for writing the ordered runs in the selected partition in the workfile storage devices, and means for merging the ordered runs into a single sorted run.
摘要:
An arrangement for providing gracefully degraded services on the Internet under overloaded conditions, involving tagging user request to indicate the status of said request and providing appropriate level of degraded services gracefully responsive to said tagging information.
摘要:
A method (and structure) for monitoring continual range queries against events includes decomposing each range query with one or more predefined virtual constructs, building a query index, and using the query index to match an event with the range queries.
摘要:
In a system including a collection of cooperating cache servers, such as proxy cache servers, a request can be forwarded to a cooperating cache server if the requested object cannot be found locally. An overload condition is detected if for example, due to reference skew, some objects are in high demand by all the clients and the cache servers that contain those hot objects become overloaded due to forwarded requests. In response, the load is balanced by shifting some or all of the forwarded requests from an overloaded cache server to a less loaded one. Both centralized and distributed load balancing environments are described.
摘要:
Techniques are provided for performing structural joins for answering containment queries. Such inventive techniques may be used to perform efficient structural joins of two interval lists which are neither sorted nor pre-indexed. For example, in an illustrative aspect of the invention, a technique for performing structural joins of two element sets of a tree-structured document, wherein one of the two element sets is an ancestor element set and the other of the two element sets is a descendant element set, and further wherein each element is represented as an interval representing a start position and an end position of the element in the document, comprises the following steps/operations. An index is dynamically built for the ancestor element set. Then, one or more structural joins are performed by searching the index with the interval start position of each element in the descendant element set.