Patent classifications
G06F12/109
Address hashing in a multiple memory controller system
In an embodiment, a system may support programmable hashing of address bits at a plurality of levels of granularity to map memory addresses to memory controllers and ultimately at least to memory devices. The hashing may be programmed to distribute pages of memory across the memory controllers, and consecutive blocks of the page may be mapped to physically distant memory controllers. In an embodiment, address bits may be dropped from each level of granularity, forming a compacted pipe address to save power within the memory controller. In an embodiment, a memory folding scheme may be employed to reduce the number of active memory devices and/or memory controllers in the system when the full complement of memory is not needed.
Coherence-based cache-line Copy-on-Write
A method of performing a copy-on-write on a shared memory page is carried out by a device communicating with a processor via a coherence interconnect. The method includes: adding a page table entry so that a request to read a first cache line of the shared memory page includes a cache-line address of the shared memory page and a request to write to a second cache line of the shared memory page includes a cache-line address of a new memory page; in response to the request to write to the second cache line, storing new data of the second cache line in a second memory and associating the second cache-line address with the new data stored in the second memory; and in response to a request to read the second cache line, reading the new data of the second cache line from the second memory.
FAULT BUFFER FOR TRACKING PAGE FAULTS IN UNIFIED VIRTUAL MEMORY SYSTEM
A system for managing virtual memory. The system includes a first processing unit configured to execute a first operation that references a first virtual memory address. The system also includes a first memory management unit (MMU) associated with the first processing unit and configured to generate a first page fault upon determining that a first page table that is stored in a first memory unit associated with the first processing unit does not include a mapping corresponding to the first virtual memory address. The system further includes a first copy engine associated with the first processing unit. The first copy engine is configured to read a first command queue to determine a first mapping that corresponds to the first virtual memory address and is included in a first page state directory. The first copy engine is also configured to update the first page table to include the first mapping.
FAULT BUFFER FOR TRACKING PAGE FAULTS IN UNIFIED VIRTUAL MEMORY SYSTEM
A system for managing virtual memory. The system includes a first processing unit configured to execute a first operation that references a first virtual memory address. The system also includes a first memory management unit (MMU) associated with the first processing unit and configured to generate a first page fault upon determining that a first page table that is stored in a first memory unit associated with the first processing unit does not include a mapping corresponding to the first virtual memory address. The system further includes a first copy engine associated with the first processing unit. The first copy engine is configured to read a first command queue to determine a first mapping that corresponds to the first virtual memory address and is included in a first page state directory. The first copy engine is also configured to update the first page table to include the first mapping.
System and Method for Managing Secure Files in Memory
A data access manager is provided on a computing device to manage access to secure files stored in memory. The data access manager intercepts function calls from applications to the memory management unit and determines whether an application is allowed to access secure data stored in the memory of the computing device. When an initial request to map the data is received, the data access manager maps both secure data and clear data, obtaining pointers to both secure and clear data. When an application has permission to access the requested data, the data access manager returns the pointer to the clear data. When an application does not have permission to access the requested data, the data access manager returns the pointer to the secure data.
IMPROVING MEMORY ACCESS HANDLING FOR NESTED VIRTUAL MACHINES
Systems and methods for memory management for nested virtual machines. An example method may comprise running, by a host computer system, a Level 0 hypervisor managing a Level 1 virtual machine running a Level 1 hypervisor, wherein the Level 1 hypervisor manages a Level 2 virtual machine, wherein the Level 2 virtual machine is associated with a Peripheral Component Interconnect (PCI) device; generating, by the Level 0 hypervisor, a Level 1 page table by combining records from the guest page table with records from a host page table maintained by the Level 0 hypervisor; generating a Level 2 page table comprising a plurality of Level 2 page table entries; and causing a device driver of the Level 2 virtual machine to use the Level 2 page table for second level address translation.
Memory sharing via a unified memory architecture
A method and system for sharing memory between a central processing unit (CPU) and a graphics processing unit (GPU) of a computing device are disclosed herein. The method includes allocating a surface within a physical memory and mapping the surface to a plurality of virtual memory addresses within a CPU page table. The method also includes mapping the surface to a plurality of graphics virtual memory addresses within an I/O device page table.
Memory sharing via a unified memory architecture
A method and system for sharing memory between a central processing unit (CPU) and a graphics processing unit (GPU) of a computing device are disclosed herein. The method includes allocating a surface within a physical memory and mapping the surface to a plurality of virtual memory addresses within a CPU page table. The method also includes mapping the surface to a plurality of graphics virtual memory addresses within an I/O device page table.
Throttling access to high latency hybrid memory DIMMs
A throttling engine throttles access to a high latency hybrid memory. A request is received for partition mapping of a virtual address for an R/W memory page. An entry is added to a partition page table that maps a virtual address to a physical address and comprises access information that is R/W. A throttled flag is set in an entry of a partition page extension table. The throttle entry corresponds to the entry. The access information is saved in an original access part of the partition page extension table, and the access information is replaced with an R value. Upon application fault receipt, a throttling test is performed on an address of the application fault. If the throttling test is false, the fault is passed through to an operating system fault handler and the throttling fault stage is ended, otherwise, a delay is implemented for slowing access to the memory.
ARTIFICIAL INTELLIGENCE CHIP AND DATA OPERATION METHOD
An artificial intelligence chip and a data operation method are provided. The artificial intelligence chip receives a command carrying first data and address information and includes a chip memory, a computing processor, a base address register, and an extended address processor. The base address register is configured to access an extended address space in the chip memory. The extended address processor receives the command. The extended address processor determines an operation mode of the first data according to the address information. When the address information points to a first section of the extended address space, the extended address processor performs a first operation on the first data. When the address information points to a section other than the first section of the extended address space, the extended address processor notifies the computing processor of the operation mode and the computing processor performs a second operation on the first data.