Home > Storage > Data Storage Essentials > Storage Admin > The Next Generation PowerMax - Balancing Performance with Efficiency and Sustainability > Glossary of Terms
Terminology | Equivalent term | Definition |
Dell PowerMax 2500 | PowerMax 2500 is the next generation entry level NVMe scale-out offering for the PowerMax family. It is designed to provide customers with a small ultra-dense storage footprint (8 PBe in only 10U) | |
Dell PowerMax 8500 | PowerMax 8500 is the next generation flagship NVMe scale-out offering of the PowerMax family. It features a true disaggregated storage architecture which can deliver up to 18 PBe of capacity to customers. | |
Dell PowerMax family | The PowerMax family refers to the Dell NVMe-based, mission-critical data storage offering. The family includes the first-generation offerings PowerMax 2000 and 8000, and next generation offerings PowerMax 2500 and 8500 | |
Disk group | Disk group | A shared physical resource pool of physical drives of the same technology, size, and performance characteristics. The drives inside the disk group pools are dived into subgroups called clusters. Disk Groups are a foundation level component of Flexible RAID. |
Disaggregated Storage Architecture | Disaggregated Storage | Disaggregated storage decouples a storage array’s compute and storage components so they can be scaled and provisioned separately. |
Dynamic Media Enclosure | DME | DME refers to the NVMe-oF attached enclosures which house the physical storage drives of the system. All DMEs in the system can be accessed by all compute nodes via internal NVMe-oF SAN topologies. |
Effective capacity (in Terabytes) | TBe | This capacity measurement includes the benefits of thin provisioning, inline compression, deduplication, and space-efficient copies. |
Endpoint | Endpoint | A point on a fabric in which an initiator or receiver can be attached |
Flexible RAID | Flexible RAID | A new RAID distribution model enabled by the disaggregation of compute and storage in the PowerMax system. It provides active / active RAID protection across storage pools in the system DMEs |
Global Cache | Global Cache | The global cache is the total size of user accessible memory across all PowerMax Nodes. This is pooled resource which is accessible by all nodes in the PowerMax system by using Remote Direct Memory Access (RDMA) |
Hybrid memory, message-based fabric | Hybrid Fabrics / NVMe/RDMA | Hybrid fabrics are transfer NVMe data and commands using a combination of encapsulated message and memory-based fabrics. These fabrics are often referred to as NVMe/RDMA (Remote Direct Memory Access) fabrics. NVMe/RDMA is considered the highest performing of the NVMe-oF transport types because applications can access remote memory without the involvement of the host operating system or the network software stack. It can transfer data directly without involving the kernel and does not consume additional CPU cycles to process transactions. NVMe over InfiniBand (NVMe/IB) and NVMe/RDMA over Converged Ethernet (NVMe/RoCE) are examples of hybrid fabrics |
Memory based fabric | In memory-based fabrics, NVMe commands, responses, and data use shared memory between the host and storage subsystem. This method was primarily specified in the original NVMe base standard, which defined how NVMe commands and responses are mapped to the queues in shared memory in a host over the PCIe interface. This method is known as a memory-based transport model in which commands, responses, and data are transferred between host memory and storage by performing explicit memory read and write operations using Direct Memory Access (DMA) over the internal high-speed PCIe fabric. The NVMe/PCIe transport specification defines and describes the mechanisms for how this process is accomplished. | |
Message based fabrics | Message based fabrics | In message-based fabrics, NVMe commands, responses, and data are encapsulated and placed into fabric-dependent packets for transmission over distance to a remote storage subsystem. NVMe/TCP and NVMe/FC are examples of message-based fabrics |
Next generation PowerMax | NextGen | The next generation PowerMax systems are comprised of the PowerMax 2500 and PowerMax 8500. |
Node | Node | Contains the compute elements of the second generation PowerMax storage system – CPU, memory, and I/O modules. Roughly equivalent to a first generation PowerMax director |
Node Pair | Node Pair | Two PowerMax nodes – roughly equivalent to a first generation PowerMax engine. |
Non-Volatile Memory Express (NVMe) | NVMe | NVMe is a command set and its associated storage-interface standards that specify efficient access to data storage devices and systems based on Non-Volatile Memory (NVM). |
NVMe Namespace | Namespace | Namespace is a generic term that refers to a contiguous area of storage that the host can access directly. It represents the mapping of the associated nonvolatile memory to a formatted logical block address (LBA) range. An NVMe namespace is equivalent to a SCSI logical unit (LU) or volume. |
NVMe over Fabric | NVMe-oF | NVM Express over Fabrics (NVMe-oF) defines a common architecture that supports a range of memory and message-based fabrics for the transport of NVMe data and commands. |
NVMe over PCIe | NVMe/PCIe | NVMe/PCIe is an extension of the NVMe base specification that defines the binding of the NVMe protocol to memory-based fabrics using Peripheral Component Interface Express (PCIe). |
NVMe over Fibre Channel | NVMe/FC | NVMe/FC is an extension of the NVMe base specification that defines the binding of the NVMe protocol to message-based fabrics using the Fibre Channel transport protocol (FC). NVMe/FC is an example of a message-based fabric |
NVMe over InfiniBand | NVMe/IB | NVMe/IB is an extension of the NVMe base specification that defines the binding of the NVMe protocol to hybrid memory, message-based fabrics using Ethernet and the InfiniBand transport protocol. NVMe/IB is an example of a hybrid memory, message based (NVMe/RDMA) fabric |
NVMe over TCP | NVMe/TCP | NVMe/TCP is an extension of the NVMe base specification that defines the binding of the NVMe protocol to message-based fabrics using Ethernet and the Transport Control Protocol (TCP). NVMe/TCP is an example of a message-based fabric |
Peripheral Component Interconnect Express (PCIe) | PCIe | A high-performance peripheral I/O bus architecture employed in enterprise servers, storage devices, cloud computing equipment, PCs, mobile devices, industrial computing, and automation systems, and Internet of Things (IoT) applications. It is not an overstatement when said that our modern interconnected world would not exist if not for PCIe. |
PCIe Switched Fabric | PCIe Fabric | A switched fabric architecture that uses PCIe switches to connect the PCIe root to various PCIe endpoints |
PowerMaxOS 10.X
| PowerMaxOS 10.X | The PowerMaxOS 10.X release is the primary storage software which manages the next generation PowerMax systems – the PowerMax 2500 and PowerMax 8500. It cannot be installed on previous generation PowerMax or VMAX systems |
RAID Width | RAID width | This is the minimum quantity of physical disks which comprise a specific RAID protection scheme. Also referred to as a RAID fault domain. |
Root Complex | PCIe Root or Root | The primary connection mechanism which connects the CPU(s) and memory to the PCIe switched fabric. |
Storage Area Network | SAN | A Storage Area Network (SAN) is a specialized, high-speed network that provides network access to storage devices. SANs are typically composed of hosts, switches, and storage arrays that are interconnected using a variety of technologies, topologies, and protocols. |
Scale out | Scale out | Scale out refers to adding nodes to grow performance |
Scale up | Scale up | Scale up refers to adding additional capacity in to the PowerMax storage pools |
Unisphere™ for PowerMax | Unisphere | Unisphere for PowerMax is a graphical user interface that enables management and monitoring of both first and second generation PowerMax arrays along with legacy VMAX All Flash, VMAX3™, and VMAX 1 or 2 arrays. Unisphere for PowerMax also provides REST API interface for managing and controlling the storage system. |
Usable capacity (in Terabytes) | TBu | This refers to the amount of physical drive capacity available in the array, considering the RAID efficiency of the RAID type in use. |