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SSD RAID is a methodology to boost solid-state drive (SSD) performance and is commonly used to protect data by distributing redundant data blocks across SSDs.
A redundant array of independent disks (RAID) is a virtualization technology of data storage that combines multiple physical storage drives into single or multiple logical units for data redundancy and optimization performance.
Nowadays, most motherboards have built-in RAID, but it is unnecessary and can plug RAID controllers into motherboards where RAID is unavailable. Floor-standing RAID units are widely used for large storage area networks (SANs), with huge amounts of data and cache memory, and RAID is also used in gaming PCs and by business users.
While SSDs are more reliable than hard disk drives (HDDs), there is no moving part for an SSD, so it is still prone to failure, which can result in data loss. SSD RAID is primarily used for protection against such data loss, which can lead to further performance gains. Further, SSD RAID is useful and effective for applications where data read/write speed and protection is particularly important.
SSD RAID Features
SSD RAID’s reliable and performance-oriented storage solutions come with essential tools and storage delivery mechanisms. Some of the SSD RAID features are given below.
Faster Data Read/Write Speeds
SSD RAID is widely recommended for its fast data read and write ability, where SSD RAID is superior to a single SSD. The RAID array configured with multiple SSDs can greatly impact the reading and writing of data.
For example, the striping method enables a single file to be distributed across numerous SSDs, increasing data read/write speeds by dispersing continuous data into multiple drives for access. RAID 0 is popular as a striped volume with at least two drives and can increase capacity by adding multiple SSDs capacity together.
SSD RAID’s fault tolerance is a particularly attractive feature that attracts many enterprises. The mirroring capability ensures fault tolerance and RAID levels depend on the number of SSDs used in a system device.
Fault tolerance is commonly used to protect data by distributing redundant data blocks across multiple SSDs and can be configured to protect data integrity through backup or correction methods.
SSD RAID management tools simplify the configuration and management of RAID controllers and enable them to be managed through a user interface (UI) or command-line interface (CLI). The dedicated software detects and monitors multiple SSD statuses and allows the configuration of the controllers. That said, the functions of SSD RAID management tools may vary by platform.
How does SSD RAID Work?
SSD RAID works based on three key concepts—striping, mirroring, and parity—to improve performance and ensure higher data security.
Striping involves dividing data into blocks and spreading the blocks of data across multiple storage devices, where data is split evenly across two or more drives. This methodology allows a single file to be distributed across several SSD drives, which helps to increase data read/write speed and performance. When spread across multiple SSDs, data can be divided in various ways.
Mirroring involves duplicating the data, where data is written simultaneously to two or more separate SSDs. Copying data onto another drive enables recovering data if a single drive fails in an array; this is more effective for critical data.
Writing the same data to two or more drives makes data recovery quick and simple. When one of the drives in an array fails, the RAID controller allows duplicating the data from the good drive to a new SSD. In the event of failure, the data will immediately be available on the second drive that can operate without experiencing downtime.
SSD RAID involves parity computations for safety for performance, where data is striped across multiple SSDs. Parity computations capability is used in drive arrays for fault tolerance by computing the data in the drives and storing the results on another drive. It is generally calculated by binary or by performing a XOR (exclusive or) operation to compare a bit from one SSD with a bit from a second drive and storing the calculated results on a third drive.
Hardware RAID vs. Software RAID
Storage systems apply RAID at the whole-drive level, and redundancy is used to manage data at a finer granularity. You can accomplish this by using hardware RAID or software RAID—whichever is best for your current technology stack.
Hardware RAID needs a dedicated controller installed in the server and performed on the motherboard or a separate RAID card. RAID cards manage the RAID arrays by providing logical disks to the system. Hardware RAID allows many different RAID configurations simultaneously, and data access is usually faster with increased fault tolerance.
On the other hand, software RAID performs on the internal server, generally requiring the installation of a RAID driver or software to create and manage the RAID infrastructure. If you do not have a RAID controller and your SSDs are directly connected to the motherboard, then RAID configuration can be controlled by utility software in the operating system.
Software RAID is highly recommended for local storage, and many operating systems provide software RAID implementations. Moreover, it’s often cheaper and does not require much dedicated hardware except for the storage array.
Using SSD With Different RAID Levels
SSD RAIDS can be configured into different levels, enabling improved performance levels and data security. The Storage Networking Industry Association (SNIA) standardized RAID levels and their associated data formats.
In a RAID 0 system, all SSDs are connected into a single storage pool to combine speed for improved performance, where data is split up into blocks across the storage drives in the array. The performance can be enhanced further using multiple controllers, but you lose all of the data if any storage drive fails. A RAID 0 system is good for users who regularly back up their storage, and it is ideal for a non-critical system that needs high speed for reading and writing data.
RAID 1 systems provide more reliability, where data mirrors a second SSD. In this system, data is stored twice simultaneously by writing on both the data drive and a mirror drive. If a drive fails, it can be recovered from the mirror drive.
That said, RAID 1 performs slower and doubles the number of SSDs needed. It is ideal for critical storage and suitable for small servers, where data security is more important than performance.
RAID 2 systems use bit-level striping with dedicated Hamming code parity, and each sequential bit is stored on a different drive. It records error correction code (ECC) using Hamming code parity, which is calculated across bits; each data bit is recorded on a separate disk, and ECC codes are stored on different drives.
Despite this, RAID 2 is expensive and more complex, and it is generally not used by any commercial system.
RAID 3 uses byte-level striping with dedicated parity, where data is striped into each sequential byte on the different drives. With RAID 3, there’s high throughput for transferring large amounts of data, but much configuration may be required, even for a small file transfer.
Like RAID 2, RAID 3 requires a special controller for the synchronized storage drives, and it is generally not used by any commercial system.
RAID 4 systems use block-level striping with dedicated parity bits. If a single data block is requested, each SSD functions independently and does not require synchronization. The main advantage of RAID 4 is input and output (I/O) parallelism; one I/O read operation does not need to spread across all data drives and can be executed in parallel, which helps to improve performance.
Nowadays, RAID 4 has been widely replaced by RAID-DP, a proprietary implementation of RAID 4 with two parity disks.
RAID 5 systems use block-level data striping with distributed parity to storage drives, and it is a standard-level configuration. Parity writes and I/O operations are spread evenly across all data drives.
Moreover, RAID 5 is cost-efficient and has become popular for SSD subsystems. It increases security via parity data and improves speed by interleaving data across storage drives. Upon drive failure, subsequent reads can be calculated from the distributed parity; they will lose no data.
Similar to RAID 3, RAID 5 requires at least three drives, but the parity is distributed among all drives, unlike RAID 3’s separate parity drives.
RAID 6 systems use block-level striping with double distributed parity instead of one, which provides fault tolerance for up to two SSDs failures. It is efficient for larger drive capacities and array sizes, especially for high-availability systems.
RAID 6 requires a minimum of four storage drives and will survive even if two data drives die simultaneously. The failed drives are being replaced, but large-capacity SSDs take longer to restore.
RAID 6 is good for systems that need better performance and efficient storage with excellent security. It is similar to RAID 5 but not as widely used. It is a complex technology; rebuilding an array can take a long time.
Nested or hybrid RAID can be a good solution for some cases. Popular hybrid RAID systems include RAID 1+0 (RAID 10) and RAID 5+0 (RAID 50). RAID 10 is a combination of multiple mirrored SSDs (RAID 1) and data stripes (RAID 0) in a single array that builds with a striped set from a series of mirrored drives.
To learn more about RAID levels read: RAID Levels Explained
Top 3 SSD RAID Benefits
SSD RAID may not be necessary, but the system’s performance and speed, data security, and reliability and endurance make it a popular method of ensuring data availability and redundancy.
Performance and Speed
SSD RAID is superior in the aspect of performance. An SSD RAID array with multiple SSDs can enormously impact performance. Dividing data into blocks and spreading the blocks of data across storage devices increases read/write speeds and overall performance.
The sequential read/write speed of the SSD RAID is about twice that of a single drive. An SSD RAID configuration performs better than any mechanical drive RAID setup, and a dedicated hardware RAID controller performs better than a software-based RAID solution.
SSD RAID ensures higher data security than a single SSD. There is a risk of data loss using a single drive. In any event, if the SSD is damaged, it can destroy an entire dataset.
SSD RAID allows you to store data in multiple drives in a RAID array, so if any SSD in the array is damaged, another SSD will protect a copy of the data, and you can recover your data.
Reliability and Endurance
SSD RAID is an effective option to ensure data remains available even if individual parts fail in the system. SSD RAID can survive one or more failures in an array, and if a drive fails, it could be replaced, and the system rebuilds itself.
SSD RAID endurance can help businesses protect data and make it more reliable than a single SSD-based system.
How Does RAID Affect SSD Performance?
SSDs have become widely popular for their speed and durability to upgrade performance for notebooks, desktops, and workstations. Using grouped SSDs in RAID arrays offers additional performance gains in servers. With that, SSD RAIDs are the ideal solution for dataset applications in servers where high-performance I/O is important.
Striping distributes a single data file across several SSDs that split evenly across them, enabling high-speed storage for transaction files and increasing overall performance. Further, mirroring duplicates a data file onto multiple SSDs, which allows data recovery if a single drive fails in an array, improving data security and making data recovery quick and simple.
SSDs with a RAID configuration combine high-speed storage for data transactions and redundancy for business-critical applications. SSDs’ data transfer speeds generally range from 300 to 600 MBps for both read and write speeds, and SSD RAID can quickly increase transfer speeds up to 1,000 MBps, depending upon the configurations and the number of SSDs in the RAID array. For faster data read/write operations and working with critical data, SSD RAID improves performance and maximizes data protection.
HDD RAID vs. SSD RAID
HDD RAID and SSD RAID can be good options to improve performance and data security. Some comparisons between them are given below.
HDD RAID SSD RAID
Best for More storage and cheaper cost More reliability and faster speed
Speed Slower Faster
Reliability Less reliable, high chance of failure More reliable, less chance of failure
Storage Capacity More storage capacity Less storage capacity
Data Recovery Less complex but takes more time More complex but takes less time
Performance Overall performance is lower than SSD RAID Overall performance is higher than HDD RAID
Price Typically cheaper than SSD RAID Relatively expensive compared to HDD RAID
Is SSD RAID Worth It?
An SSD RAID array can lead to further performance gains, improved speed, and higher reliability. For businesses or large systems where computing speed and data security is an important fact and cost is not a concern, SSD RAID can be a perfect solution for them.
Who Shouldn’t Use an SSD With RAID?
SSD RAID is more expensive and can be a complex maintenance issue for beginner-level or nontechnical users.
Cost: SSDs are more expensive than HDDs, and building an SSD RAID array requires multiple SSDs. Businesses with a limited budget for their system should not use an SSD RAID, except to have extra backup storage.
Maintenance Issues: There is no doubt that SSD RAID has a conflicting maintenance issue as a defrag can affect its lifespan. For beginner-level or non-technical users, it can be extra trouble. Small businesses or personal systems with a limitation of expert personnel should avoid any RAID systems or SSD RAID.
Speed Is Not Necessary: A single SSD is fast enough for general use. In most cases, fast computing speed is optional for small systems and personal uses, where a single SSD can perform well.
Best 3 RAID SSDs Available
OWC SSD Mercury Elite Pro Dual Mini Portable RAID
OWC SSD Mercury Elite Pro Dual Mini is the overall best based on performance and price. The Mercury Elite Pro Dual Mini is a high-performance portable RAID—a perfect combination of price, power, and speed.
It has user-selectable modes RAID 0 and RAID 1, which can be configured as the user needs. With RAID 0 mode, the Mercury Elite Pro Dual Mini provides fast data transfer speeds up to 989 MBps, and RAID 1 delivers greater data redundancy from mirrored disks.
OWC offers five Mercury Elite Pro Dual Mini Portable RAID SSD models 480GB, 1TB, 2TB, 4TB, and 8TB; pricing starts from $229.00 with the 480GB.
It can be a good choice for high-demand applications with packing dual-drive, USB 3.1 Gen 2, and a bus-powered form factor. OWC SSD Mercury Elite Pro Dual Mini delivers the performance and flexibility to meet powerful workflow for pros working with rich media content.
SanDisk Professional G-RAID Shuttle SSD
SanDisk Professional G-RAID Shuttle SSD is best for performance and ideal for large capacity. It is a consolidated storage that enables a fast storage powerhouse to help streamline workflows.
The RAID array houses one 2.5″ SSD in each bay and is generally preconfigured in RAID 5 but supports RAID 0, 1, 10, and 50. It can provide transfer speeds up to 2800 MBps using the Thunderbolt 3 interface and can be used with USB 3.2.
SanDisk offers G-RAID Shuttle SSD with capacities of 8TB, 16TB, and 32TB. You can combine up to five devices using two Thunderbolt 3 ports.
SanDisk Professional G-RAID Shuttle SSD is an ideal choice for large capacity, and the RAID implementation delivers excellent reliability. It provides a versatile and flexible storage solution, ensuring maximum performance and support for multi-stream workflows.
Glyph Atom RAID SSD
Glyph Atom RAID SSD is designed to deliver a portable RAID storage solution at an affordable price, starting from $99.95 (500GB). Its lightweight aluminum body keeps data safe from rough handling.
Glyph Atom RAID SSD contains two M.2 SSDs, a mobile/bus-powered storage device that does not need an external power supply. It has four capacity variants between a 500GB, 1TB, 2TB, or 4TB drive but allows only Thunderbolt 3 port access.
Atom RAID is configured for RAID 0 to maximize performance and cannot be reconfigured in other RAID modes. It is unreliable in the case of a drive failure, and there is no provision for connecting to monitors, but it is a perfect solution for large data transfers in a short time. Glyph Atom RAID is an ultra-fast mobile RAID providing up to 950MBps transfer speed, making it an ideal portable RAID storage.
Do You Need an SSD RAID?
There are many SSD RAID options available in the market with useful features, which should be considered based on the needs and demand of your business as well as the cost. While an SSD RAID system can improve the overall speed and performance of your business’s data management, it can be an expensive and overly complex option that is not ideal for smaller businesses or personal use.