摘要:
A method and apparatus for performing efficient interprocess communication (IPC) in a computer system. With this invention, a memory region called the IPC transfer region is shared among all processes of the system to enable more efficient IPC. The unique physical address of the region is mapped into a virtual address from each of the address spaces of the processes of the system. When one of the processes needs to transfer data to another of the processes, the first process stores arguments describing the data in the region using the virtual address in its address space that maps into the unique physical address. When the other or second process needs to receive the data, the second process reads the data from the second region using the virtual address in its memory space that maps into the unique physical address. With this invention, in most cases, control of the IPC transfer region occurs automatically without any kernel intervention.
摘要:
In a computer system, a method and apparatus for scheduling activities' access to a resource with minimal involvement of the kernel of the operating system. More specifically, a “next bid” is maintained, and this parameter identifies the highest bid for the resource by any activity not currently accessing the resource. The accessing activity then compares its bid, which can be time varying, with the “next bid” to determine whether it should release the resource to another activity. The “next bid” can be accessed without any system calls to the operating system. This allows the activity to determine whether to relinquish control to the system without the necessity of communication between the two. Likewise, the operating system can access the bid of the accessing activity without explicit communication. This allows the system to determine whether to preempt the accessing activity without the necessity of communication between the two.
摘要:
Systems, especially operating systems, are becoming more complex to the point where maintaining them by humans is becoming nearly impossible. Many corporations have recognized this trend and have begun investing in autonomic technology. Autonomic technology allows a piece of software to monitor, diagnose, and repair itself. This can be used for improved performance, reliability, maintainability, security, etc. Disclosed herein is a mechanism to allow operating systems to hot swap a piece of operating system code, while continuing to offer to the user the service which that code is providing. This can be used, for examples, to increase the performance of an application or to fix a detected security hole live without bringing the machine down. Some autonomic ability will be mandatory in next generation operating system for without it they will collapse under their own complexity. The invention offers a key component of being able to achieve autonomic computing.
摘要:
To dynamically update an operating system, a new factory object may have one or more new and/or updated object instances. A corresponding old factory object is then located and its version is checked for compatibility. A dynamic update procedure is then executed, which includes (a) changing a factory reference pointer within the operating system from the old factory object to the new factory object. For the case of updated object instances, (b) hot swapping each old object instance for its corresponding updated object instance, and (c) removing the old factory object. This may be performed for multiple updated object instances in the new factory object, preferably each separately. For the case of new object instances, they are created by the new factory and pointers established to invoke them. A single factory object may include multiple updated objects from a class, and/or new object instances from different classes, and the update may be performed without the need to reboot the operating system.
摘要:
A method for allowing a content provider to restrict access to data without having to trust a service provider. With this invention a content provider is able to restrict access to data to a specific client using a specific machine. A content provider generates a first key which is used to encrypt a second key where the second key will only be encrypted if the user has a one-time password. The encrypted second key is then stored on the client machine. When the user desires to access the data of the content provider, the second key is decrypted and used to access the data.
摘要:
A method and apparatus for displaying a spreadsheet on a display device in a computer system to facilitate easy recognition of errors. More specifically, with this invention one cell is selected, and there is a visual indication of such selection. Further, there is also a visual indication of those cells having data that either affects or depends upon the data in the selected cell. There is also a different visual indication for each level of dependency relative to the selected cell. For example, selected cell A may be immediately dependent upon cells B and C, where cell B may in turn be dependent upon cells D, E and F. Cells B and C are at the first level of dependency while cells D, E and F are at the second level of dependency. Thus, cells B and C may have a different marking or shading than cells D, E and F. The number of dependency levels to be displayed can be chosen by the user. The number of paths of cells to be displayed from a selected cell to a leaf cell can also be chosen by the user. This invention also provides for the simultaneous display of formulas in all cells.