A computer system stores metadata that is used to identify physical memory devices that store randomly-accessible data for memory of the computer system. In one approach, access to memory in an address space is maintained by an operating system of the computer system. Stored metadata associates a first address range of the address space with a first memory device, and a second address range of the address space with a second memory device. The operating system manages processes running on the computer system by accessing the stored metadata. This management includes allocating memory based on the stored metadata so that data for a first process is stored in the first memory device, and data for a second process is stored in the second memory device.

A storage device for performing an access authority control and an operating method thereof are disclosed. The storage device including processing circuitry configured to store a plurality of security information associated with the plurality of namespaces in response to a command from the host, each of the security information including virtual machine information associated with a corresponding one of the plurality of virtual machines and unique information associated with the corresponding virtual machine, the virtual machine information including an identifier for the corresponding virtual machine, and the unique information including unique information uniquely set for the corresponding virtual machine, extract at least first information by decoding a data access request received from the host device, and abort processing of the data access request based on the security information and the extracted at least one first information.

Systems and methods for determining an access pattern in a computing system. Accesses to a file may contain random accesses and sequential accesses. The file may be divided into multiple regions and the accesses to each region are tracked. The access pattern for each region can then be determined independently of the access patterns of other regions of the file.

A memory system having a plurality of memory components and a controller, operatively coupled to the plurality of memory components to: store data in the memory components; communicate with a host system via a bus; service the data to the host system via communications over the bus; communicate with a processing device that is separate from the host system using a message passing interface over the bus; and provide data access to the processing device through communications made using the message passing interface over the bus.

Techniques of memory tiering in computing devices are disclosed herein. One example technique includes retrieving, from a first tier in a first memory, data from a data portion and metadata from a metadata portion of the first tier upon receiving a request to read data corresponding to a system memory section. The method can then include analyzing the data location information to determine whether the first tier currently contains data corresponding to the system memory section in the received request. In response to determining that the first tier currently contains data corresponding to the system memory section in the received request, transmitting the retrieved data from the data portion of the first memory to the processor in response to the received request. Otherwise, the method can include identifying a memory location in the first or second memory that contains data corresponding to the system memory section and retrieving the data from the identified memory location.

An example method of virtualizing a hardware accelerator in a host cluster of a virtualized computing system includes: commanding, at an initiator host in the host cluster, a programmable expansion bus device to reconfigure as a virtual accelerator based on specifications of a hardware accelerator in a target host of the host cluster; executing, in the programmable expansion bus device, software to emulate the virtual accelerator as connected to an expansion bus of the initiator host; receiving, at the programmable expansion bus device, compute tasks from an application executing in the initiator host; and sending, to the target host, the compute tasks for processing by the hardware accelerator.

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.

Systems, apparatuses, and methods related to three tiered hierarchical memory systems are described herein. A three tiered hierarchical memory system can leverage persistent memory to store data that is generally stored in a non-persistent memory, thereby increasing an amount of storage space allocated to a computing system at a lower cost than approaches that rely solely on non-persistent memory. An example apparatus may include a persistent memory, and one or more non-persistent memories configured to map an address associated with an input/output (I/O) device to an address in logic circuitry prior to the apparatus receiving a request from the I/O device to access data stored in the persistent memory, and map the address associated with the I/O device to an address in a non-persistent memory subsequent to the apparatus receiving the request and accessing the data.

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.

High performance space efficient distributed storage is disclosed. For example, a distributed storage volume (DSV) is deployed on a plurality of hosts, with a first host storing a local cache, and a storage controller executing on a processor of the first host receives a request to store a first file. The first file is stored to the local cache. The DSV is queried to determine whether a second file that is a copy of the first file is stored in the DSV. In response to determining that the DSV lacks the second file, the first file is transferred from the local cache to the DSV and then replicated to a second host of the plurality of hosts. In response to determining that the second file resides in the DSV, a reference to the second file is stored in the DSV and then replicated to the second host.