Volatile memory and non-volatile memory are two fundamentally different types of computer memory, primarily distinguished by their behavior in retaining data when power is removed. In this article, we will take a closer look at the differences between volatile and non-volatile memory.
The primary distinction between these memory types lies in their data retention behavior, speed, and use cases. Volatile memory provides fast, temporary storage for active data, while nonvolatile memory ensures data persistence and is used for long-term storage and system integrity. Both memory types serve crucial roles in computing systems.
Quick links:
- What is volatile memory?
- Types of volatile memory hardware
- Types of volatile data
- What is non-volatile memory?
- Types of non-volatile storage hardware
- Types of non-volatile data
- Crystal Group’s approach to memory
What is volatile memory?
Volatile memory is a type of computer memory that temporarily stores data and loses that data when power is removed, or the device is turned off. It is called “volatile” because the stored information is not persistent and doesn’t survive power cycles. Here are some key characteristics of volatile memory:
- Data retention: Volatile memory loses all its stored data when the power source is disconnected or turned off. This makes it unsuitable for long-term data storage.
- Speed: Volatile memory is typically much faster in terms of read and write operations compared to non-volatile memory. This speed is essential for quickly accessing and manipulating data during the operation of a computer or electronic device.
- Usage: Volatile memory is primarily used to store data that needs to be accessed quickly by the computer’s central processing unit (CPU) and other hardware components. It is used for tasks such as running applications or storing data that is actively being processed and is typically managed by the computer’s operating system.
Types of volatile memory hardware
Volatile memory hardware is typically found within or close to the CPU, this enables it to be faster and lower latency but limits its capacity. Here are some examples of volatile memory hardware:
- RAM: There are different types of Random Access Memory (RAM) that a modern computing system utilizes, the type most commonly used by the processor is Dynamic Random Access Memory (DRAM). Another type is Video RAM (VRAM), which is used for storing graphics data, textures, and frame buffers for rendering images on a display.
- Cache: CPU cache memory, including L1, L2, and L3 caches, stores frequently used data for faster access. Cache data is typically faster than RAM, because it is located within the CPU that uses it.
- Registers: Processor registers are small, fast storage locations within the CPU used for temporary data storage during computations. Being close to the computational logic allows registers to be faster than caches, but it limits their size to keep accessing them simple.
Types of volatile data
Volatile data is typically associated with the active operation of a computer or electronic device and includes various types of data:
- Session data: Web browsers, applications, and software often store session data temporarily in RAM during their operation. This data can include user inputs, open files, and temporary variables.
- Clipboard data: Copied or cut text or files placed on the clipboard for copying and pasting operations are stored in volatile memory.
- Temporary files: Temporary files created by applications and the operating system for various purposes are typically stored in volatile memory while in use. These files are deleted when no longer needed.
- Operating system state: The state of the operating system, including running processes, open files, and system variables, is maintained in volatile memory. This state is reset when the computer is rebooted.
- Network buffers: Data packets being sent or received over a network are often temporarily stored in network buffers in RAM. This data is volatile and is cleared once the network operation is completed.
- Printer queues: Data in printer queues, waiting to be printed, is stored in volatile memory until it’s sent to the printer. It’s removed from memory once printed or canceled.
Volatile data is essential for the real-time operation of computer systems and applications but should not be relied upon for long-term storage or data preservation, as it is transient and disappears when power is lost. To retain data beyond a power cycle, it should be saved to non-volatile memory devices like hard drives or solid-state drives.
What is non-volatile memory?
- Data retention: Non-volatile memory retains its stored data across power cycles and does not require a continuous power supply to maintain data integrity. This makes it suitable for storing data that needs to be preserved over time.
- Speed: Non-volatile memory is typically slower in terms of read and write operations compared to volatile memory, such as RAM. However, it offers the advantage of data persistence, which is important for tasks like storing operating system files, user data, and software applications.
- Usage: Non-volatile memory is used for a wide range of storage purposes, including secondary storage in computers (e.g., hard disk drives and solid-state drives), firmware storage in devices (e.g., system BIOS in computers), and portable storage devices (e.g., USB drives and memory cards).
- Examples: Hard Disk Drives (HDDs), Solid-State Drives (SSDs), Read-Only Memory (ROM), Flash Memory (e.g., USB drives), EEPROM.
Types of non-volatile storage hardware
Non-volatile storage is usually located within a system and connected via an interface whether it’s SATA, PCIe, SPI, etc. They allow bulk storage of data on the order of several megabytes (MB) to several terabytes (TB). They’re typically slower but more than make up for it in the amount of data that can be stored. Here are some key examples:
- Read-only memory (ROM): ROM is a type of non-volatile memory that contains firmware or software that cannot be modified by the user. This includes firmware on game consoles, smartphones, and embedded systems.
- Drives: Drives focus on bulk storage of information on the order of hundreds of gigabytes (GB) to a few terabytes (TB). Here are some current drives used in systems today:
- Solid-state drives (SSD)
- Non-volatile memory express (NVMe)
- Rotational/hard drives
- Flash memory storage devices: Flash memory is a type of non-volatile memory commonly used in USB drives, memory cards, and solid-state drives (SSDs). It stores data persistently and is widely used for portable storage and data retention.
- Non-volatile RAM (NVRAM): Some devices, like routers and network switches, use non-volatile RAM (NVRAM) to store configuration settings. NVRAM retains data even when the device is powered off.
Types of non-volatile data
Here are some common types of non-volatile data:
- File storage: Non-volatile data storage includes the files and documents stored on hard disk drives (HDDs) and solid-state drives (SSDs). These files can include documents, images, videos, music, software applications, and more.
- Operating system: The operating system (e.g., Windows, macOS, Linux) is typically stored in non-volatile memory. It includes system files, drivers, and configuration settings that are essential for the device’s operation.
- Firmware: Firmware is a type of software that is permanently stored in non-volatile memory on hardware devices. It controls the device’s functions and may include BIOS firmware on computers, firmware on printers, routers, and other embedded systems.
- Bootloader: A bootloader is software that initializes the boot process of a computer or device. It is stored in non-volatile memory and is responsible for loading the operating system into RAM during startup.
- User data: Non-volatile memory stores user-specific data, such as profiles, settings, and preferences. This includes data related to user accounts, customization options, and personalization settings.
- Configuration settings: Various devices and software applications store configuration settings and preferences in non-volatile memory. Examples include network settings, display preferences, and software configurations.
- BIOS/UEFI settings: Basic Input/Output System (BIOS) or Unified Extensible Firmware Interface (UEFI) settings on computers are stored in non-volatile memory. These settings control hardware and system parameters.
- Archival data: Data intended for long-term archival purposes, such as historical records, legal documents, and digital archives, is stored in non-volatile memory to ensure its preservation over time.
- System backups: Backup copies of data and system configurations are stored in non-volatile memory to recover from data loss or system failures.
Non-volatile data is critical for preserving important information and system functionality. Unlike volatile data, which is temporary and transient, non-volatile data remains accessible and intact across power cycles, making it suitable for long-term storage and data retention.
Crystal Group’s approach to memory
Whether it’s a single drive to store your operating system and user files, a self-encrypting drive to protect your data at rest, or a large number of drives to enable RAID, data recorders, and network area storage (NAS), Crystal Group will partner with you to meet your storage needs. Our solution-driven engineering team is constantly innovating to provide our customers and their end users the exact system that is required.