International Business Machines Corporation

Domenico Di Giulio

Bernardo Pastorelli

Riccardo Rossi

Silvano Lutri

Bruno Portaluri

Eliana Cerasaro

Alessandro Capomassi

Ricardo Rossi

Providing access to a shared resource in a computing environment involves maintaining a timestamp for each shared resource, the timestamp representing the time the resource was last accessed. Then, detecting if the resource is reserved before obtaining access to the resource, by reading the resource timestamp, and if the timestamp represents a future time relative to the current time, indicating that the resource is reserved and delaying access to the resource. If the resource is unreserved, then accessing the resource by reading the resource timestamp to detect any changes in the timestamp since the last reading; if unchanged, then accessing the resource. If the resource is unreserved, then obtaining exclusive access to the resource by reserving the resource by incrementing its timestamp by a reservation period; accessing the resource; and resetting the resource timestamp to the current time.

Mechanisms for obtaining access to shared resources using a single timestamp technique

A mechanism is provided for scheduling a workload on a computer. The mechanism receives, in the computer, one or more workload-related variables. The mechanism further receives, in the computer, one or more trigger values for at least one of the one or more workload-related variables. Moreover, the mechanism determines, from the workload-related variables and their triggering values, one or more conditions under which one or more tasks are to be performed on the computer. In addition, the mechanism acquires a status value of at least one of the one or more workload-related variables at regular intervals and performs a task when a status value of a workload-related variable attains the triggering value for the task.

Scheduling a workload based on workload-related variables and triggering values

Mechanisms for providing exclusive access to shared resources in a database

A database comprising a plurality of tables is interrogated by generating a database query, and a data map, the data map describing the structure of table instances implicated in the database query. Next, the database query is submitted to the database. A response is received from the database. The data map is traversed so as to iteratively apply a data extraction process to components of the response corresponding to each table instance associated with the database query, thereby extracting the required data from the response.

Database query processing method and system

A load balancing system and a corresponding computer-readable medium are proposed. The load balancing system is used in environments (e.g., implementing a licensing management application) wherein each client is associated with a preferred server storing specific information for the client. Each client periodically detects a workload and a response time of all the servers. The client selects a subset of nearest servers (according to their response times). The server in that subset with the lowest workload is set as an eligible server. Whenever a ratio between the workload of the preferred server and the workload of the eligible server exceeds a predefined threshold value (e.g., 1.1), the client switches to the eligible server (transferring the corresponding specific information). The system of the invention exhibits a slow dynamic, and tends to reach a steady condition (wherein the specific information of the clients is not continuously moved across the system).

Slow-dynamic load balancing system and computer-readable medium

A process for generating SQL queries to retrieve requested information from a database, whilst applying requested search filters, involving defining a 'base' query, which is the simplest SQL query that can be executed to retrieve the information requested by the user (i.e. without applying any search filter), and then use a separate module for each search filter to detect the existence of the table that is required to apply that filter, and possibly add a 'WHERE' condition that includes the required table using a sub-query. For each module, if the table required to filter a particular attribute exists in the current query, the &#x201c;WHERE&#x201d; condition is added on that table, without adding any sub-query. If on the other hand the required table does not exist in the current query, a sub-query that navigates associations from the tables involved in the current query to the required on is added, and the &#x201c;WHERE&#x201d; condition is added to the required table within the sub-query.

Database query generation method and system

A method () and system for controlling use of software programs on multiple workstations of a network. An agent running on each workstation detects () any new process (using a kernel hooking technique), which is started in response to the request of execution of a program (). The process is suspended () and an authorization to run the program is requested () to an associated metering server. The metering server compares () the current usage of the product with the respective authorized conditions of use, and answers () the agent granting or denying the authorization to run. The process is accordingly resumed (), in order to enable the program to start, or aborted (), so as to prevent execution of the program. In any case, the program is not stopped (but it is prevented from starting); this avoids killing the program while it is performing potentially risky operations.

System for controlling use of digitally encoded products

A load balancing method and a corresponding system are proposed. The load balancing method is used in environments (e.g., implementing a licensing management application) wherein each client is associated with a preferred server storing specific information for the client. Each client periodically detects a workload and a response time of all the servers. The client selects a subset of nearest servers (according to their response times). The server in that subset with the lowest workload is set as an eligible server. Whenever a ratio between the workload of the preferred server and the workload of the eligible server exceeds a predefined threshold value (e.g., 1.1), the client switches to the eligible server (transferring the corresponding specific information). The method of the invention exhibits a slow dynamic, and tends to reach a steady condition (wherein the specific information of the clients is not continuously moved across the system).

Slow-dynamic load balancing method

A method () and system for controlling use of software programs on multiple workstations of a network. An agent running on each workstation detects () any new process (using a kernel hooking technique), which is started in response to the request of execution of a program (). The process is suspended () and an authorisation to run the program is requested () to an associated metering server. The metering server compares () the current usage of the product with the respective authorised conditions of use, and answers () the agent granting or denying the authorisation to run. The process is accordingly resumed (), in order to enable the program to start, or aborted (), so as to prevent execution of the program. In any case, the program is not stopped (but it is prevented from starting); this avoids killing the program while it is performing potentially risky operations.

Growing community of inventors

Rome, Italy

Domenico Di Giulio