Data Management Glossary
Storage Tiering
What is Storage Tiering?
Storage Tiering refers to a technique of moving less frequently used data, also known as cold data, from higher performance storage such as SSD to cheaper levels of storage or tiers such as cloud or spinning disk.
The term “storage tiering” arose from moving data around different tiers or classes of storage within a storage system, but has expanded now to mean tiering or archiving data from a storage system to other clouds and storage systems.
Storage tiering is now considered a core feature of modern storage systems and recently has become part of default configuration for next generation storage like AWS FSx ONTAP. Block-level data storage solutions include: NetApp FabricPool and Dell PowerScale CloudPools.
Storage-agnostic data management and data tiering have emerged as more and more enterprise organizations adopt hybrid, multi-cloud, and edge IT infrastructure strategies. See also cloud tiering and choices for cloud data tiering.
Storage Tiering Cuts Costs Because 70%+ of Data is Cold
As data grows, data storage costs grow. It is easy to think the solution is more efficient storage. Or simply buy more storage. But data management is the real solation. Typically over 70% of data is cold and has not been accessed in months, yet it sits on expensive storage hardware or cloud infrastructure and consumes the same backup resources as hot data.
As a result, data storage costs are rising, backup times are slowing and disaster recovery (DR) is unreliable. The sheer bulk of this data makes it difficult to leverage newer options like Flash and Cloud.
Data Tiering Was Initially Used within a Storage Array
Data Tiering was initially a technique used by storage systems to reduce the cost of data storage by tiering cold data within the storage array to cheaper but less performant options. For example, moving data that has not been touched in a year or more from an expensive Flash tier to a low-cost SATA disk tier.
Typical storage tiers within a storage array or on-premises storage device include:
- Flash or SSD: A high-performance storage class but also very expensive. Flash is usually used on smaller data sets that are being actively used and require the highest performance.
- SATA Disks: High-capacity disks with lower performance that offer better price per GB vs SSD.
- Secondary Storage, often Object Storage: Usually a good choice for capacity storage – to store large volumes of cool data that is not as frequently accessed, at a much lower cost.
Increasingly, enterprise IT organization are looking at another option: tiering or archiving data to a public cloud.
- Public Cloud Storage: Public clouds currently have a mix of object and file storage options. The object storage classes such as Amazon S3 and Azure Blob (Azure Storage) provide tremendous cost efficiency and all the benefits of object storage without the headaches of setup and management.
- Cloud NAS has also become increasingly popular, but if unstructured data is not well managed, data storage costs will be prohibitive.
Cloud Storage Tiering is now Popular
Tiering and archiving less frequently used data or cold data to public cloud storage classes is now more popular. This is because customers can leverage the lower cost storage classes within the cloud to keep the cold data and promote them to the higher cost storage classes when needed.
For example, data can be archived or tiered from on-premises NAS to Amazon S3 Infrequent Access or Amazon Glacier for low ongoing costs. Later you can move it to Amazon EFS or FSX when you want to operate on it and need performance.
Cloud isn’t just low-cost data storage
The cloud offers more than low-cost data storage. Advanced security features such immutable storage can prevent ransomware. Cloud native services from analytics to machine learning can drive value from your unstructured data.
To take advantage of these capabilities and to ensure you’re not treating the cloud as just a cheap storage locker, tiered data must be accessible natively in the cloud without requiring third-party software. This requires the right approach to storage tiering, which is file-tiering, not block-tiering.
Block Tiering Creates Unnecessary Costs, Lock-In
Block-level storage tiering was first introduced as a technique within a storage array to drive efficiency by leveraging a mix of technologies such as more expensive SSD disks and cheaper SATA disks.
Block storage tiering breaks a file into various metadata blocks that contain information about the file, and data blocks that are chunks of the original file. Block-tiering moves less used cold blocks to lower, less expensive tiers, while hot blocks and metadata are typically retained in the higher, faster, and more expensive storage tiers.
Block tiering is a technique used within the storage operating system or filesystem and is proprietary. Storage vendors offer block tiering to reduce the cost of their storage environment. Many storage vendors are now expanding block tiering to move data to the public cloud or on-premises object storage.
Block storage tiering, often called CloudPools, such as NetApp FabricPool and Dell EMC Isilon CloudPools, is done inside the storage operating system as a proprietary solution. It has several limitations when it comes to efficiency of reuse and efficiency of storage savings.
- Firstly, with block tiering, the proprietary storage filesystem must be involved in all data access since it retains the metadata and has the “map” to putting the file together from the various blocks.
- This also means that the cold blocks that are moved to a lower tier or the cloud cannot be directly accessed from the new location without involving the proprietary filesystem. This is because the cloud does not have the metadata map and the other data blocks, file context and attributes to put the file together.
- So, block tiering is a proprietary approach that often results in unnecessary rehydration of the data.
With block storage tiering, the only way to access data in the cloud is to run the proprietary storage file system in the cloud which adds to costs. Also, many third-party applications such as backup software that operate at a file level require the cold blocks to be brought back or rehydrated. This defeats the purpose of tiering to a lower cost storage and erodes the potential savings.
For more details, read the white paper: Block vs. File-Level Tiering and Archiving.
Learn more about Komprise Data Tiering.
What is storage tiering and how does it work?
Storage tiering is the process of automatically moving data between storage tiers based on usage, age, performance needs, and cost. Frequently accessed “hot” data stays on fast premium storage, while inactive “cold” data is moved to lower-cost tiers such as object storage or cloud. This helps organizations balance performance and cost.
Why is storage tiering especially important now?
Storage tiering is more urgent than it has ever been for three converging reasons.
- Eterprise unstructured data is growing at 55-65% annually and tripling between 2023 and 2026, meaning the volume of cold data sitting on expensive primary storage is compounding every year without intervention.
- Dnterprise SSD and NAND flash prices rose 53-58% quarter-over-quarter in Q1 2026 according to TrendForce, making the cost of keeping cold data on flash-based primary storage significantly higher than in recent years. Third, AI initiatives are competing for the same high-performance storage capacity that cold data is occupying, meaning organizations that have not tiered their cold data are paying premium storage prices for inactive files while their AI workloads run on constrained capacity.
Storage tiering is increasingly important because enterprises are facing rising, rapid unstructured data growth, tighter IT budgets, and growing AI infrastructure demands. The right approach to storage tiering helps preserve expensive high-performance storage for active workloads while reducing waste from inactive data. File-level Intelligent Tiering rather than block-based vendor tiering, can reclaim 70% or more of primary storage capacity and deliver substantial cost savings without disrupting users or applications.
Source: TrendForce enterprise SSD pricing February 2026
Source: Komprise State of Unstructured Data Management report
What is the difference between storage tiering and backup or archiving?
Storage tiering is designed to optimize active storage costs by relocating cold data while preserving transparent user access. Backup focuses on recovery copies, and archiving focuses on long-term retention. The Komprise Transparent Move Technology (TMT) approach to tiering complements both strategies by reducing the amount of expensive primary storage and backup footprint required.
How does Komprise improve storage tiering?
Komprise Intelligent Tiering delivers file-level, storage-agnostic tiering that overcomes the fundamental limitations of vendor-native block-based tiering tools. Rather than operating at the block level within a single vendor’s storage operating system, Komprise scans the entire unstructured data estate across multi-vendor NAS and cloud environments using Komprise Analysis, building a complete picture of what data exists, who owns it, when it was last accessed, and how much it costs to store. Komprise Deep Analytics then uses this information as the basis for precise tiering policies: not just “move data older than 12 months” but “move all files not accessed in 90 days owned by the engineering department, except files tagged as active projects.”
When data is tiered, Komprise Transparent Move Technology moves it in its native format to any cloud or object storage destination. There are no proprietary stubs, no format conversion, and no rehydration required. Users access tiered files transparently via Dynamic Links from their original paths with no awareness that data has moved. Any authorized application or AI pipeline can read tiered data directly from object storage without any intermediary layer.
Komprise is also fully vendor-agnostic. The same tiering policies work across NetApp, Dell PowerScale, HPE, Nutanix, Qumulo, VAST Data, and any cloud storage destination including AWS S3, Azure Blob, Google Cloud Storage, and Wasabi. This eliminates the vendor lock-in that comes with native storage tiering tools and gives IT teams a unified tiering strategy across the entire storage estate regardless of which vendors are in use.
What is Komprise Flash Stretch and how does it relate to storage tiering?
The Komprise Flash Stretch Assessment is a pre-purchase analysis designed specifically for organizations facing a storage refresh decision or evaluating new flash capacity purchases. Before committing to buying additional expensive flash or NAS hardware, Komprise Analysis scans the environment to identify exactly how much cold unstructured data is currently occupying primary flash storage and quantifies precisely how much of that capacity can be reclaimed through intelligent tiering. The assessment shows projected savings across different cloud and object storage destinations and models the specific cost impact of tiering under different policy scenarios.
At current flash prices, Komprise has identified savings opportunities of $350,000 or more per petabyte for organizations that right-place cold unstructured data before committing to new hardware. In many cases the Flash Stretch Assessment identifies enough reclaimable capacity to defer or eliminate a planned flash purchase entirely, turning a capital expenditure into avoided cost. Storage tiering and Flash Stretch work together: the assessment quantifies the opportunity, and Komprise Intelligent Tiering executes it automatically on an ongoing basis so capacity stays optimized over time rather than requiring a one-time intervention.
How does storage tiering support AI initiatives and data pipelines?
AI training, inferencing, and RAG pipelines need fast, accessible storage for active datasets. When 60-70% of primary storage is occupied by cold unstructured data, AI workloads compete with inactive files for the same expensive, high-performance capacity. This forces organizations to buy more primary storage than AI workloads actually require, inflating infrastructure costs and complicating capacity planning.
Komprise Intelligent Tiering addresses this by continuously right-placing cold data off primary storage automatically, freeing premium capacity for AI workloads where performance genuinely matters. Tiered data does not disappear from the data estate. It remains indexed in the Global Metadatabase, accessible via Dynamic Links, and stored in its native format on open standards-based object storage. This means an AI pipeline that needs historical research files, archived imaging data, or past project records can access tiered data directly without any rehydration step or format conversion, at the same time that active AI workloads run at full speed on uncontested primary storage.
For enterprises building RAG pipelines or curating AI training datasets, Komprise Smart Data Workflows can identify and deliver the right tiered data to AI platforms automatically, based on metadata and tag criteria, ensuring that the full value of the unstructured data estate, not just recently created hot data, is available to AI systems without any performance or cost penalty for accessing tiered content.
What is the difference between block-level tiering and Komprise file-level Intelligent Tiering?
Block-level tiering, offered natively by storage vendors including NetApp FabricPool and Dell PowerScale CloudPools, operates at the storage block level within a proprietary file system. It can reduce costs within a single vendor’s environment but has no awareness of business context, creates vendor lock-in, and typically requires rehydration before data can be read by external applications. File-level tiering, as delivered by Komprise, operates with full awareness of file metadata and business context across any storage vendor, stores data in native format, and eliminates rehydration entirely.
| Capability | Block-Level Tiering (NetApp FabricPool, Dell CloudPools) | Komprise File-Level Intelligent Tiering |
|---|---|---|
| Tiering granularity | Block level, no file context | File level, full metadata and business context |
| Vendor scope | Single vendor only | Any NAS vendor, any cloud destination |
| Policy flexibility | I/O frequency based | File age, owner, type, size, tags, Deep Analytics queries |
| Data format on destination | Proprietary blocks, vendor dependent | Native format always, open standards |
| Rehydration required | Often yes, for external access | Never |
| Vendor lock-in | High | None |
| User access to tiered data | Via proprietary file system only | Transparent via Dynamic Links, any path |
| AI pipeline access | Rehydration required | Direct access in native format, no overhead |
| Multi-vendor support | No | Yes, any NAS and cloud environment |
| Searchable after tiering | No | Yes, via Global Metadatabase |
| Policy based on business tags | No | Yes, via Deep Analytics and custom tags |
| Pre-purchase savings modeling | No | Yes, via Flash Stretch Assessment |
| Cost savings typical | Varies, limited by single vendor scope | 70%+ of primary NAS capacity reclaimed |
The core difference is that block-level tiering optimizes within a vendor’s own ecosystem using storage metrics. Komprise Intelligent Tiering optimizes across the entire storage estate using business context, delivering greater savings, no lock-in, and direct AI pipeline access.