Hot Storage vs. Cold Storage

Hot Storage vs. Cold Storage

When it comes to data storage, all data isn’t equal. After all, the data you use daily doesn’t need the same level of protection or ease of access as long-term hot storage vs. cold storage backup. A large percentage of a business’ data remains unleveraged due to data management and security challenges, which highlights the need to implement a data storage strategy. Keep reading to learn the difference between hot storage and cold storage, the pros and cons of each, and how to choose the best option for your company.


What Is Hot Storage?

The term “hot storage” refers to data that must be accessible immediately. This is a good option if the data is mission-critical and you can’t wait for it when you need it. How fast the data can be accessed depends on how many routes it needs to take to reach its destination. Data processed closest to the source offers the fastest speed. Information that has further to go to reach its destination will be slower. 

Information with the hottest storage requirements may use solid-state drives, which are intended for reduced latency and greater transactional rates than traditional hard drives. On the other hand, hard disk drives are better suited to circumstances where the drive is heavily utilized because of its superior resilience in the face of frequent read/write cycles. 

Where Is Hot Storage Information Located?

Hot archival information is located in an edge-storage configuration. In this approach, files are stored on servers within close range of their intended user population. This provides better network latency and bandwidth when accessing these resources from remote locations—especially at peak times when traffic is highest. 

Edge archival is a type of edge computing that helps companies reduce their costs by simplifying and reducing infrastructure. Edge archival also improves security. With the information stored close to the user, there is less of a chance a hacker can gain access to it while it is in transit. Historically, information access for mobile devices was limited due to speed. Now, these devices can access information efficiently through an edge server. Additional benefits include: 

  • Reduces Latency: Storing information on the edge minimizes lag time for requesting it. 
  • Better Scalability: Edge archival can be scaled up and down as needed.
  • Better Security: Since information is stored locally rather than over a centralized cloud system, it can be protected more easily from cyberattacks
  • Better Privacy: Edge archival keeps data private. It does this by storing it in a physically separate location from the rest of the network. 

When to Use Hot Storage vs. Cold Storage

Hot data storage workloads demand rapid and consistent reaction times regardless of the archival media used. Interactive video editing, web content, and online transactions are just a few examples. Hot archival services are also designed for workloads involving a large number of tiny transactions, such as telemetry information capture, messaging, and information translation.

The Benefits of Hot Storage

Hot data archival technology uses non-volatile memory. Information stored will not be lost even in the event of a power outage. Its speed makes it ideal for a variety of use cases. Additional benefits include:

  • Real-Time Processing: Hot data can be utilized in real-time processing applications that require fast response times such as CRM, ERP, and e-commerce platforms 
  • Reliability: Information is stored on SSDs, which are more reliable than HDDs. Hot storage is backed up more frequently than cold archival. Thus, there is less risk of losing important information in the event of business disruption.
  • Speed: The faster storage speeds allow information to be accessed quickly 

AWS Hot Archival Options

Amazon AWS offers three types of hot information archival: Elastic Block Storage (EBS), General Purpose Instances (GPI), and Provisioned IOPS (PIOPS).

  • EBS: Amazon EBS is an archival service that leverages local archival and durable disk drives to protect information. It provides persistent block-level archival volumes, which means users can access their information as if it were sitting on a traditional hard drive. Amazon EBS delivers the same durability as standard EBS volumes but with the added benefits of block-level access and quicker provisioning times.
  • General Purpose Instances: GPI is meant to provide fast response times on demand, while PIOPS provides consistent low latency access to the disk subsystem to be more suitable for heavy transactional workloads such as web servers.
  • Provisioned IOPS: This archival type is excellent for applications with erratic spikes in I/O requests. Examples include databases and virtual machines. Provisioned IOPS SSD is perfect for storing hot information because it provides predictable speed and higher read and write throughput levels.

Microsoft Azure Hot Storage Options

Microsoft Azure offers several different types of hot archival. For example, Microsoft Azure Blob Storage is object-based and provides the highest level of durability for storing unstructured data such as images or videos. It also offers Hot Add, which allows you to increase performance by adding new disks while your virtual machine is running without incurring downtime with an online resizing operation. Lastly, Microsoft’s innovative SSDs can provide high IOPS at low latency through caching that supports applications like SQL Server OLTP read workloads from disk efficiently, in most cases without requiring expensive PCIe flash cards.

Google Cloud Hot Storage Options

Google Cloud offers three types of hot archival: 1) persistent disks backed by SSDs, 2) memory-optimized instances with high bandwidth to avoid disk I/O, and 3) HDD Snapshots. 

Google Cloud’s persistent disks provide the best performance for information-intensive workloads. Memory-optimized instances run applications at peak levels because there is no disk I/O involved. It runs entirely on RAM, making it faster and cheaper than other options.

What Is Cold Storage?

Information that is rarely used or accessed is a good candidate for cold archival. This is typically information that must be retained for compliance purposes. The information is often stored long-term and sometimes indefinitely. Cold archival is cheaper and slower than hot archival. 

When to Use Cold Storage

A common use case for this type of storage is archived projects. Archived project documents don’t need to be accessed frequently. However, companies may want to refer to them later for research or reference. Storing legal and HR information is another use case. Often these departments have long-term archival requirements. Cold archival keep this information available for audits.

The Benefits of Cold Storage

There is no need to pay premium prices for data that doesn’t require frequent access. Cold archival is a way to save money. Additional benefits include:

  • Stores inactive data more economically
  • Reduces costs
  • Simplifies archival option
  • Meets regulatory requirements efficiently
  • Prevents overloading primary repositories with inactive data

Regulatory and Compliance Cold Storage Requirements

Some industries have strict rules for storing data. Healthcare and financial service industries must keep information for specified timeframes. Cold archival keep this information available to meet those requirements. Many of these regulations may come with additional requirements for cold data archival such as audit trails that log anytime someone accesses the information.

Where to Store Cold Data

There are numerous methods for properly managing cold archival. Utilizing low-cost archival, leveraging cloud cold archival, monitoring cold data use annually, and adopting data archival automation are all common methods. 

Slow hard drives and tapes are frequently seen as suitable cold data archival mediums. However, all disks and tapes should be tested regularly to ensure they still work. Companies should also monitor device lifespan and retire aging devices before they fail. Not all cold data should be kept indefinitely. Evaluate data yearly to ensure resources are being used effectively. 

AWS Cold Storage Options

AWS offers five different types of cold archival options. The first is Amazon Glacier Cold Storage, which uses inexpensive, but slow retrieval times for data that you don’t need to access often or immediately. AWS also has three redundant backup systems called S3 Standard-Infrequent Access (S3 STANDARDIA), Reduced Redundancy Storage (RRS), and One Zone-Storage Class Memory Cache for Flash/SSD Instances(ZSC). Finally, there’s Elastic Block Store with its cool capabilities like snapshots and cloning virtual hard disks.

Microsoft Azure Cold Storage Options

Azure Cool Blob Storage provides options for storing data that does not need redundancy or replication. This option does not provide retention guarantees, meaning you do not know how long your content will be stored before it’s deleted. However, this archival plan comes at an attractive price point when compared to its competitors, which can make up for the lack-of-retention guarantee if needed. Cool Blob archival only stores cool (nonactive) blocks on disks instead of hot (active) ones. Cool Blob Storage offers infinite snapshot capabilities. This type of archival allows public access through anonymous authentication.

Google Cloud Cold Storage Options

Google Cloud offers two classes of cold storage options: Google Nearline Storage and Google Coldline Storage. The differences are as follows:

Google Nearline Storage: Nearline storage is best for information that is needed infrequently but regularly (typically once per month or less). Common use cases for this type of storage are media archives, storing regular backups, or employing it as a disaster recovery facility. 

Google Coldline Storage: Coldline storage works best for information needed less than once per year. An example use case is storage for outdated backups.

What Is Warm Storage?

Warm data archival caches less frequently accessed information to avoid spikes in demand. Data stored here are updated every few hours, days, weeks, months, or years depending on the frequency specified. It allows companies to have access to their most recent files without having to perform frequent backups. Warm data archival may include cloud-based backup services to free up space on an organization’s primary servers and archival systems that are cheaper but not online all the time.

When To Use Warm Storage

Use this form of archival for information that doesn’t require frequent access. Examples include data for statistical modeling or time series forecasting. Another example is for data that needs to be replicated and synchronized across multiple servers.

A common scenario for warm archival is to bridge data access after mergers and acquisitions. Mergers and acquisitions often lead to separate archival infrastructures with incompatible file formats. Warm archival acts as a bridge by providing read-only access using one format while storing files originating from both legacy systems on tape.

The Benefits of Warm Storage

Warm data is much easier to back up. The backups must only encompass the changes made since the last full one. Restoring from backup is also easier with warm data archival. Information in warm archival is already online and waiting in its original location after being restored. Warm archival uses “chunking,” which makes restoring data faster than cold archival. 

AWS Warm Storage Options

AWS offers two archival options for data that is not in active use: 

  • Archive Storage, which stores infrequently accessed data at lower costs than standard cold storage. This option provides cost savings of up to 80% with reduced durability and availability compared to AWS’s standard archival.
  • Regional Cold Storage (RRS), where you can store the most rarely used items on tape or disk media near your geographic location. You pay less per gigabyte of capacity when storing archives this way but will experience longer retrieval times—typically 24 hours or more.

Microsoft Azure Warm Storage Options

Azure Cool Storage is designed for high I/O workloads that don’t require frequent access. Cool archival keeps inactive hot and cold data in the cloud.

Google Cloud Warm Storage Options

Nearline is a low-cost archival option for infrequently accessed data. Data stored in Nearline can be accessed in less than two minutes. However, if it goes offline, companies may experience a 24-hour delay before all replicas are reestablished.

How AI Is Redefining Data Storage

Hot storage vs. cold storage isn’t always straightforward. This is especially true with new technology such as artificial intelligence (AI) and the internet of things (IoT). Each of these technologies generates massive amounts of data. AI requires significant data to improve the predictive environment’s accuracy levels, where data must be ingested, stored, and prepared. As a result, these technologies have varying archival requirements based on capacity, throughput, latency, IOPS, and other factors. AI and IoT technology will likely need to address hot storage vs. cold storage along with data growth requirements.

Hot Storage vs. Cold Storage Costs

In general, hot archival is more expensive than cold archival. Hot data requires the fastest and most expensive archival because it’s accessed more frequently. Cold data is stored on slower media that is cheaper to purchase.

Hot Storage vs. Cold Storage vs. Warm Storage: Which Is Right for You?

Speed is the most important factor to consider when evaluating archival options. Every company is different, so there is no right answer. Ideally, all three should be used, it’s just a matter of defining how much of which. Below are additional factors to consider:

Hot Storage: Hot archival is the short-term or working memory, and it contains active files that are still being used. Hot data archival is best used when an application requires fast access to the data—for example, online transaction processing (OLTP). An OLTP system must process transactions in real time. Hot archival makes this possible. Another example is a data warehouse. These data stores must process large queries. Information stored in data warehouses is often used for analytics. Hot archival makes this information available instantly.

Cold Storage: Cold archival is the long-term archival of data, and it is not intended to be accessed often. This type of archival is typically used for long-term backups and archiving purposes. 

The most common use case for cold data archival is to provide secondary or backup copies of hot (or warm) data. Cold archival is also ideal for organizations with strict compliance needs. Some companies may benefit from using cold archival for offsite backups. Additional scenarios include:

  • Offline backups of data from a live application or operating system. 
  • Archive storage for data that has been migrated to an online archiving solution but needs to be retrieved offline occasionally (e.g., regulatory compliance). 
  • Data retention policies where an organization must retain all records for a given amount of time before they can be deleted. 
  • Legal or forensic information.

Warm Storage: Warm archival is a mix between cold and hot archival because it can be used as either one depending on your needs and preferences at any given time. This type of archival provides a good compromise between the two options that can be useful in many situations.

How To Get the Most From Your Data Storage Strategy

Most archival vendors use artificial intelligence to enable automatic tiered data storage. Companies define the rules and triggers that the AI software uses to distribute. 

A tiered strategy typically works as follows: For storing frequently used data, in-memory archival and solid-state drives are frequently used as the primary tier. A secondary tier is used to store data that is only used infrequently on less expensive drives. Another tier is dedicated to cold data archival on low-cost slow disk drives and tapes. Using data tiers ensures that data is constantly optimized and distributed to achieve the best results at the lowest cost.

The sheer volume of data generated by companies requires highly resilient and flexible archival options. Data archival is the first line of defense for preserving mission-critical information. Companies have a variety of archival options. When evaluating hot storage vs. cold storage, speed is the determining factor. Following the above tips can help determine which option is best for your company.