Systems and methods for memory management for 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 which manages a Level 2 virtual machine. The Level 1 hypervisor may detecting execution of an operation that prevents modification to a set of entries in a Level 2 page table and generate a shadow page table where each shadow page table entry of the plurality of shadow page table entries maps a Level 2 guest virtual address of a Level 2 address space associated with the Level 2 virtual machine to a corresponding Level 1 guest physical address of a Level 1 address space associated with the Level 1 virtual machine. The Level 0 hypervisor may generate a Level 0 page table.

In one embodiment, an apparatus includes a processor comprising an address translation cache (ATC); a shared work queue (SWQ) associated with the ATC, and a port to couple to a host processor over a Peripheral Component Interconnect Express (PCIe)-based link. The apparatus also includes circuitry to receive address translation information from a memory management unit of the host processor that includes virtual memory address to physical memory address translations, store the address translation information in the ATC, receive an invalidation command from the host processor indicating an invalidation of address translation information stored in the ATC, modify the address translation information in the ATC based on the invalidation command, and store completion data in a memory location indicated by the invalidation command.

A peripheral proxy subsystem is placed between multiple hosts, each having a root controller, and single root I/O virtualization (SR-IOV) peripheral devices that are to be shared. The peripheral proxy subsystem provides a root controller for coupling to the endpoint of the SR-IOV peripheral device or devices and multiple endpoints for coupling to the root controllers of the hosts. The peripheral proxy subsystem maps the virtual functions of an SR-IOV peripheral device to the multiple endpoints as desired to allow the virtual functions to be allocated to the hosts. The physical function of the SR-IOV peripheral device is managed by the peripheral proxy device to provide the desired number of virtual functions. The virtual functions of the SR-IOV peripheral device are then presented to the appropriate host as a physical function or a virtual function.

Apparatuses, systems, and techniques to manage memory arrays. In at least one embodiment an application programming interface (API) is performed to disassociate a virtual address indicated by the API from a corresponding physical address.

Embodiments of apparatuses, methods, and systems for unified address translation for virtualization of input/output devices are described. In an embodiment, an apparatus includes first circuitry to use at least an identifier of a device to locate a context entry and second circuitry to use at least a process address space identifier (PASID) to locate a PASID-entry. The context entry is to include at least one of a page-table pointer to a page-table translation structure and a PASID. The PASID-entry is to include at least one of a first-level page-table pointer to a first-level translation structure and a second-level page-table pointer to a second-level translation structure. The PASID is to be supplied by the device. At least one of the apparatus, the context entry, and the PASID entry is to include one or more control fields to indicate whether the first-level page-table pointer or the second-level page-table pointer is to be used.

Systems and methods of tracking page state changes are provided. An input/output is communicatively coupled to a host having a memory. The I/O device receives a command from the host to monitor page state changes in a region of the memory allocated to a process. The I/O device, bypassing a CPU of the host, modifies data stored in the region based on a request, for example, received from a client device via a computer network. The I/O device records the modification to a bitmap by setting a bit in the bitmap that corresponds to a location of the data in the memory. The I/O device transfers contents of the bitmap to the CPU, wherein the CPU completes the live migration by copying sections of the first region indicated by the bitmap to a second region of memory. In some implementations, the process can be a virtual machine, a user space application, or a container.

Systems, apparatuses, and methods related to media management, including “garbage collection,” in memory or storage systems or sub-systems, such as solid state drives, are described. For example, a criticality value can be determined and used as a basis for managing a garbage collection operation on a data block. A controller or the system or sub-system may determine that a criticality value associated with performing a garbage collection operation satisfies a condition. Based on determining that the condition is satisfied, a parameter associated with performing the garbage collection operation can be adjusted. The garbage collection operation is performed on the data block stored on the memory component using the adjusted parameter.

Examples provide a method of communication between a client application and a filesystem server in a virtualized computing system. The client application executes in a virtual machine (VM) and the filesystem server executes in a hypervisor. The method includes: allocating, by the client application, first shared memory in a guest virtual address space of the client application; creating a guest application shared memory channel between the client application and the filesystem server upon request by the client application to a driver in the VM, the driver in communication with the filesystem server, the guest application shared memory channel using the first shared memory; sending authentication information associated with the client application to the filesystem server to create cached authentication information at the filesystem server; and submitting a command in the guest application shared memory channel from the client application to the filesystem server, the command including the authentication information.

Methods and systems for a storage environment are provided. One method includes splitting storage of a plurality of zoned solid-state drives (ZNS SSDs) into a plurality of physical zones (PZones) across a plurality of independent media units of each ZNS SSD, the PZones visible to a first tier RAID (redundant array of independent disks) layer; generating a plurality of RAID zones (RZones), each RZone having a plurality of PZones; presenting one or more RZones to a second tier RAID layer by the first tier RAID layer for processing read and write requests using the plurality of ZNS SSDs; and utilizing, by the first tier RAID layer, a parity PZone at each ZNS SSD for storing parity information corresponding to data written in one or more PZone corresponding to a RZone presented to the second tier RAID layer and storing the parity information in a single parity ZNS SSD.

Methods, systems, and apparatuses provide support for multiple address spaces in order to facilitate data movement. One apparatus includes an input/output memory management unit (IOMMU) comprising: a plurality of memory-mapped input/output (MMIO) registers that map memory address spaces belonging to the IOMMU and at least a second IOMMU; and hardware control logic operative to: synchronize the plurality of MMIO registers of the at least the second IOMMU; receive, from a peripheral component endpoint coupled to the IOMMU, a direct memory access (DMA) request, the DMA request to a memory address space belonging to the at least the second IOMMU; access the plurality of MMIO registers of the IOMMU based on context data of the DMA request; and access, from the IOMMU, a function assigned to the memory address space belonging to the at least the second IOMMU based on the accessed plurality of MMIO registers.