Patents by Inventor Sanjeev Ghai

Sanjeev Ghai has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6920521
    Abstract: A move engine and operating system transparently reconfigure physical memory to accomplish addition, subtraction, or replacement of a memory module. The operating system stores FROM and TO real addresses in unique fields in memory that are used to virtualize the physical address of the memory module being reconfigured and provide the reconfiguration in real-time through the use of hardware functionality and not software. Using the FROM and TO real addresses to select a source and a target, the move engine copies the contents of the memory module to be removed or reconfigured into the remaining or inserted memory module. Then, the real address associated with the reconfigured memory module is re-assigned to the memory module receiving the copied contents, thereby creating a virtualized physical mapping from the addressable real address space being utilized by the operating system into a virtual physical address space. During the process of moving the memory contents, the operating system stalls.
    Type: Grant
    Filed: October 10, 2002
    Date of Patent: July 19, 2005
    Assignee: International Business Machines Corporation
    Inventors: Ravi Kumar Arimilli, John Steven Dodson, Sanjeev Ghai, Kenneth Lee Wright
  • Publication number: 20050132148
    Abstract: A data processing system includes a system memory, one or more processing cores, and a memory controller that controls access to a system memory. The memory controller includes a memory speculation mechanism that stores historical information regarding prior memory accesses. In response to a memory access request, the memory controller speculatively initiates access to the system memory based upon the historical information in the memory speculation mechanism in advance of receipt of a coherency message indicating that the memory access request is to be serviced by reference to the system memory.
    Type: Application
    Filed: December 10, 2003
    Publication date: June 16, 2005
    Applicant: International Business Machines Corp.
    Inventors: Ravi Arimilli, Sanjeev Ghai, Warren Maule
  • Publication number: 20050132147
    Abstract: A data processing system includes one or more processing cores, a system memory having multiple rows of data storage, and a memory controller that controls access to the system memory and performs supplier-based memory speculation. The memory controller includes a memory speculation table that stores historical information regarding prior memory accesses. In response to a memory access request, the memory controller directs an access to a selected row in the system memory to service the memory access request. The memory controller speculatively directs that the selected row will continue to be energized following the access based upon the historical information in the memory speculation table, so that access latency of an immediately subsequent memory access is reduced.
    Type: Application
    Filed: December 10, 2003
    Publication date: June 16, 2005
    Applicant: International Business Machines Corporation
    Inventors: Ravi Arimilli, Sanjeev Ghai, Warren Maule
  • Patent number: 6907494
    Abstract: A processor contains a move engine and a memory controller contains a mapping engine that, together, transparently reconfigure physical memory to accomplish addition, subtraction, or replacement of a memory module. A mapping engine register stores current and new real addresses that enable the engines to virtualize the physical address of the memory module being reconfigured and provide the reconfiguration in real-time through the use of hardware functionality and not software. Using the current and new real addresses to select a source and a target, the move engine copies the contents of the memory module to be removed or reconfigured into the remaining or inserted memory modules. Then, the real address associated with the reconfigured memory module is re-assigned to the memory module receiving the copied contents, thereby creating a virtualized physical mapping from the addressable real address space being utilized by the operating system into a virtual physical address space.
    Type: Grant
    Filed: October 10, 2002
    Date of Patent: June 14, 2005
    Assignee: International Business Machines Corporation
    Inventors: Ravi Kumar Arimilli, John Steven Dodson, Sanjeev Ghai, Kenneth Lee Wright
  • Patent number: 6904490
    Abstract: A processor contains a move engine and mapping engine that transparently reconfigure physical memory to accomplish addition, subtraction, or replacement of a memory module. A mapping engine register stores FROM and TO real addresses that enable the engines to virtualize the physical address of the memory module being reconfigured and provide the reconfiguration in real-time through the use of hardware functionality and not software. Using the FROM and TO real addresses to select a source and a target, the move engine copies the contents of the memory module to be removed or reconfigured into the remaining or inserted memory module. Then, the real address associated with the reconfigured memory module is re-assigned to the memory module receiving the copied contents, thereby creating a virtualized physical mapping from the addressable real address space being utilized by the operating system into a virtual physical address space.
    Type: Grant
    Filed: October 10, 2002
    Date of Patent: June 7, 2005
    Assignee: International Business Machines Corporation
    Inventors: Ravi Kumar Arimilli, John Steven Dodson, Sanjeev Ghai, Kenneth Lee Wright
  • Publication number: 20050055528
    Abstract: A data processing system having a physically addressed cache of disk memory is disclosed. The data processing system includes multiple processing units. The processing units have volatile cache memories operating in a virtual address space that is greater than a real address space. The processing units and the respective volatile memories are coupled to a storage controller operating in a physical address space that is equal to the virtual address space. The processing units and the storage controller are coupled to a hard disk via an interconnect. The storage controller, which is coupled to a physical memory cache, allows the mapping of a virtual address from one of the volatile cache memories to a physical disk address directed to a storage location within the hard disk without transitioning through a real address. The physical memory cache contains a subset of information within the hard disk.
    Type: Application
    Filed: December 12, 2002
    Publication date: March 10, 2005
    Applicant: International Business Machines Corporation
    Inventors: Ravi Arimilli, John Dodson, Sanjeev Ghai, Kenneth Lee Wright
  • Publication number: 20040215891
    Abstract: A method and system for speculatively pre-fetching data from a memory. A memory controller on a data bus “snoops” data requests put on the data bus by a bus control logic. Based on information in the header of the data request, such as transaction type, tag, transaction size, etc., a speculative pre-fetch is made to read data from the memory associated with the memory controller. If the speculative fetch turns out to be correct, then the memory controller makes an assumption that the pre-fetch was too conservative (non-speculative), and a pre-fetch for a next data request is performed at an earlier more speculative time. If the speculative fetch turns out to be incorrect, then the memory controller makes an assumption that the pre-fetch was too speculative (made early), and a pre-fetch for a next data request is performed at a later less speculative time.
    Type: Application
    Filed: April 28, 2003
    Publication date: October 28, 2004
    Applicant: International Business Machines Corporation
    Inventors: John Steven Dodson, James Stephen Fields, Sanjeev Ghai, Jeffrey Adam Stuecheli
  • Publication number: 20040117589
    Abstract: A data processing system having no system memory is disclosed. The data processing system includes multiple processing units. The processing units have volatile cache memories operating in a virtual address space that is greater than a real address space. The processing units and the respective volatile memories are coupled to a storage controller operating in a physical address space that is equal to the virtual address space. The processing units and the storage controller are coupled to a hard disk via an interconnect. The storage controller, which is coupled to a physical memory cache, allows the mapping of a virtual address from one of the volatile cache memories to a physical disk address directed to a storage location within the hard disk without transitioning through a real address. The physical memory cache contains a subset of information within the hard disk.
    Type: Application
    Filed: December 12, 2002
    Publication date: June 17, 2004
    Applicant: International Business Machines Corp.
    Inventors: Ravi Kumar Arimilli, John Steven Dodson, Sanjeev Ghai, Kenneth Lee Wright
  • Publication number: 20040117588
    Abstract: An access request for a data processing system having no system memory is disclosed. The data processing system includes multiple processing units. The processing units have volatile cache memories operating in a virtual address space that is greater than a real address space. The processing units and the respective volatile memories are coupled to a storage controller operating in a physical address space that is equal to the virtual address space. The processing units and the storage controller are coupled to a hard disk via an interconnect. The storage controller, which is coupled to a physical memory cache, allows the mapping of a virtual address from one of the volatile cache memories to a physical disk address directed to a storage location within the hard disk without transitioning through a real address. The physical memory cache contains a subset of information within the hard disk.
    Type: Application
    Filed: December 12, 2002
    Publication date: June 17, 2004
    Applicant: International Business Machines Corporation
    Inventors: Ravi Kumar Arimilli, John Steven Dodson, Sanjeev Ghai, Kenneth Lee Wright
  • Publication number: 20040117587
    Abstract: A hardware managed virtual-to-physical address translation mechanism for a data processing system having no system memory is disclosed. The data processing system includes multiple processing units. The processing units have volatile cache memories operating in a virtual address space that is greater than a real address space. The processing units and the respective volatile memories are coupled to a storage controller operating in a physical address space. The processing units and the storage controller are coupled to a hard disk via an interconnect. The hard disk contains a virtual-to-physical translation table for translating a virtual address from one of said volatile cache memories to a physical disk address directed to a storage location in the hard disk without transitioning through a real address.
    Type: Application
    Filed: December 12, 2002
    Publication date: June 17, 2004
    Applicant: International Business Machines Corp.
    Inventors: Ravi Kumar Arimilli, John Steven Dodson, Sanjeev Ghai, Kenneth Lee Wright
  • Publication number: 20040117583
    Abstract: An apparatus for influencing process scheduling in a data processing system capable of utilizing a virtual memory processing scheme is disclosed. The data processing system includes multiple processing units. The processing units have volatile cache memories operating in a virtual address space that is greater than a real address space. The processing units and the respective volatile memories are coupled to a storage controller operating in a physical address space that is equal to the virtual address space. The processing units and the storage controller are coupled to a hard disk via an interconnect. The storage controller, which is coupled to a physical memory cache, allows the mapping of a virtual address from one of the volatile cache memories to a physical disk address directed to a storage location within the hard disk without transitioning through a real address. The physical memory cache contains a subset of information within the hard disk.
    Type: Application
    Filed: December 12, 2002
    Publication date: June 17, 2004
    Applicant: International Business Machines Corporation
    Inventors: Ravi Kumar Arimilli, John Steven Dodson, Sanjeev Ghai, Kenneth Lee Wright
  • Publication number: 20040117590
    Abstract: An aliasing support for a data processing system having no system memory is disclosed. The data processing system includes multiple processing units. The processing units have volatile cache memories operating in a virtual address space that is greater than a real address space. The processing units and the respective volatile memories are coupled to a storage controller operating in a physical address space. The processing units and the storage controller are coupled to a hard disk via an interconnect. The processing units contains an aliasing table for associating at least two virtual addresses to a physical disk address directed to a storage location in the hard disk. The hard disk contains a virtual-to-physical translation table for translating a virtual address from one of said volatile cache memories to a physical disk address directed to a storage location in the hard disk without transitioning through a real address.
    Type: Application
    Filed: December 12, 2002
    Publication date: June 17, 2004
    Applicant: International Business Machines Corp.
    Inventors: Ravi Kumar Arimilli, John Steven Dodson, Sanjeev Ghai, Kenneth Lee Wright
  • Publication number: 20040117591
    Abstract: A data processing system having no system memory is disclosed. The data processing system includes multiple processing units. The processing units have volatile cache memories operating in a virtual address space that is greater than a real address space. The processing units and the respective volatile memories are coupled to a storage controller operating in a physical address space that is equal to the virtual address space. The processing units and the storage controller are coupled to a hard disk via an interconnect. The storage controller allows the mapping of a virtual address from one of the volatile cache memories to a physical disk address directed to a storage location within the hard disk without transitioning through a real address.
    Type: Application
    Filed: December 12, 2002
    Publication date: June 17, 2004
    Applicant: International Business Machines Corp
    Inventors: Ravi Kumar Arimilli, John Steven Dodson, Sanjeev Ghai, Kenneth Lee Wright
  • Publication number: 20040073742
    Abstract: A move engine and operating system transparently reconfigure physical memory to accomplish addition, subtraction, or replacement of a memory module. The operating system stores FROM and TO real addresses in unique fields in memory that are used to virtualize the physical address of the memory module being reconfigured and provide the reconfiguration in real-time through the use of hardware functionality and not software. Using the FROM and TO real addresses to select a source and a target, the move engine copies the contents of the memory module to be removed or reconfigured into the remaining or inserted memory module. Then, the real address associated with the reconfigured memory module is re-assigned to the memory module receiving the copied contents, thereby creating a virtualized physical mapping from the addressable real address space being utilized by the operating system into a virtual physical address space.
    Type: Application
    Filed: October 10, 2002
    Publication date: April 15, 2004
    Applicant: International Business Machines Corp.
    Inventors: Ravi Kumar Arimilli, John Steven Dodson, Sanjeev Ghai, Kenneth Lee Wright
  • Publication number: 20040073765
    Abstract: A processor contains a move engine and a memory controller contains a mapping engine that, together, transparently reconfigure physical memory to accomplish addition, subtraction, or replacement of a memory module. A mapping engine register stores current and new real addresses that enable the engines to virtualize the physical address of the memory module being reconfigured and provide the reconfiguration in real-time through the use of hardware functionality and not software. Using the current and new real addresses to select a source and a target, the move engine copies the contents of the memory module to be removed or reconfigured into the remaining or inserted memory modules. Then, the real address associated with the reconfigured memory module is re-assigned to the memory module receiving the copied contents, thereby creating a virtualized physical mapping from the addressable real address space being utilized by the operating system into a virtual physical address space.
    Type: Application
    Filed: October 10, 2002
    Publication date: April 15, 2004
    Applicant: International Business Machines Corporation
    Inventors: Ravi Kumar Arimilli, John Steven Dodson, Sanjeev Ghai, Kenneth Lee Wright
  • Publication number: 20040073743
    Abstract: A processor contains a move engine and mapping engine that transparently reconfigure physical memory to accomplish addition, subtraction, or replacement of a memory module. A mapping engine register stores FROM and TO real addresses that enable the engines to virtualize the physical address of the memory module being reconfigured and provide the reconfiguration in real-time through the use of hardware functionality and not software. Using the FROM and TO real addresses to select a source and a target, the move engine copies the contents of the memory module to be removed or reconfigured into the remaining or inserted memory module. Then, the real address associated with the reconfigured memory module is re-assigned to the memory module receiving the copied contents, thereby creating a virtualized physical mapping from the addressable real address space being utilized by the operating system into a virtual physical address space.
    Type: Application
    Filed: October 10, 2002
    Publication date: April 15, 2004
    Applicant: International Business Machines Corp.
    Inventors: Ravi Kumar Arimilli, John Steven Dodson, Sanjeev Ghai, Kenneth Lee Wright
  • Patent number: 6678814
    Abstract: An apparatus for allocating data usage in an embedded dynamic random access memory (DRAM) device is disclosed. The apparatus for allocating data usages within an embedded dynamic random access memory (DRAM) device comprises a control analysis circuit, a data/command flow circuit, and a partition management control. The control analysis circuit generates an allocation signal in response to processing performances of a processor. Coupled to an embedded DRAM device, the data/command flow circuit controls data flow from the processor to the embedded DRAM device. The partition management control, coupled to the control analysis circuit, partitions the embedded DRAM device into a first partition and a second partition. The data stored in the first partition are different from the data stored in the second partition according to their respective usage. The allocation percentages of the first and second partitions are dynamically allocated by the allocation signal from the control analysis circuit.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: January 13, 2004
    Assignee: International Business Machines Corporation
    Inventors: Ravi Kumar Arimilli, James Stephen Fields, Jr., Sanjeev Ghai, Praveen S. Reddy, William John Starke
  • Patent number: 6606680
    Abstract: An apparatus for accessing a banked embedded dynamic random access memory device is disclosed. The apparatus for accessing a banked embedded dynamic random access memory (DRAM) device comprises a general functional control logic and a bank RAS controller. The general functional control logic is coupled to each bank of the banked embedded DRAM device. Coupled to the general functional control logic, the bank RAS controller includes a rotating shift register having multiple bits. Each bit within the rotating shift register corresponds to each bank of the banked embedded DRAM device. As such, a first value within a bit of the rotating shift register allows accesses to an associated bank of the banked embedded DRAM device, and a second value within a bit of the rotating shift register denies accesses to an associated bank of the banked embedded DRAM device.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: August 12, 2003
    Assignee: International Business Machines Corporation
    Inventors: Ravi Kumar Arimilli, James Stephen Fields, Jr., Sanjeev Ghai, Praveen S. Reddy, William John Starke
  • Patent number: 6601145
    Abstract: A multiprocessor computer system in which snoop operations of the caches are synchronized to allow the issuance of a cache operation during a cycle which is selected based on the particular manner in which the caches have been synchronized. Each cache controller is aware of when these synchronized snoop tenures occur, and can target these cycles for certain types of requests that are sensitive to snooper retries, such as kill-type operations. The synchronization may set up a priority scheme for systems with multiple interconnect buses, or may synchronize the refresh cycles of the DRAM memory of the snooper's directory. In another aspect of the invention, windows are created during which a directory will not receive write operations (i.e., the directory is reserved for only read-type operations). The invention may be implemented in a cache hierarchy which provides memory arranged in banks, the banks being similarly synchronized.
    Type: Grant
    Filed: December 27, 2000
    Date of Patent: July 29, 2003
    Assignee: International Business Machines Corporation
    Inventors: Ravi Kumar Arimilli, James Stephen Fields, Jr., Sanjeev Ghai, Guy Lynn Guthrie, Jody B. Joyner
  • Patent number: 6574719
    Abstract: An apparatus for providing concurrent communications between multiple memory devices and a processor is disclosed. Each of the memory device includes a driver, a phase/cycle adjust sensing circuit, and a bus alignment communication logic. Each phase/cycle adjust sensing circuit detects an occurrence of a cycle adjustment from a corresponding driver within a memory device. If an occurrence of a cycle adjustment has been detected, the bus alignment communication logic communicates the occurrence of a cycle adjustment to the processor. The bus alignment communication logic also communicates the occurrence of a cycle adjustment to the bus alignment communication logic in the other memory devices. There are multiple receivers within the processor, and each of the receivers is designed to receive data from a respective driver in a memory device. Each of the receivers includes a cycle delay block.
    Type: Grant
    Filed: July 12, 2001
    Date of Patent: June 3, 2003
    Assignee: International Business Machines Corporation
    Inventors: Ravi Kumar Arimilli, James Stephen Fields, Jr., Sanjeev Ghai, Praveen S. Reddy, William John Starke