Amazon EBS vs EFS: Where Does an S3-Compatible Option Fit In?

Every software architecture decision creates ripples across product performance, developer experience, and long-term business costs. Among those decisions, storage stands out as especially critical.

Pick block storage when object storage would serve just as well, and you’re likely overpaying. Lean on shared file systems where scale-out object storage would be a better fit, and you invite bottlenecks and unnecessary engineering overhead.

The core challenge is balancing performance, scale, and cost without locking yourself into an inflexible setup. Prioritize performance too heavily, and you burn money. Focus too much on cutting costs, and your system may stall under pressure. Scale without strategy, and storage management turns into a distraction rather than an enabler for product growth.

That's why understanding when to use EBS, EFS, or an S3-compatible option like Archil isn't just technical trivia—it's an essential architectural strategy.

Amazon EBS Explained: Elastic Block Store for High-Performance Storage

What is cloud-based block storage?

Block storage is a foundational concept in cloud-hosted data persistence. It works by emulating the behavior of a physical hard drive by exposing raw storage volumes to the operating system. A **block** is simply a fixed-size chunk of data: a sequence of bytes that represent the smallest unit of storage the system can read or write.

This foundational data model powers Amazon EBS, where AWS manages the underlying infrastructure and handles replication, durability, and performance optimization. Paired with your operating system, which manages the file system layer, this abstraction allows cloud block storage to function like a local disk drive, delivering fast and low-latency access.

How to use Amazon EBS?

Amazon EBS provides scalable, high-performance block storage that attaches directly to Amazon Elastic Compute Cloud(EC2) instances. You can choose from various volume types optimized for general-purpose workloads, high IOPS, or throughput-heavy operations.

Once an EBS volume is attached to a compute instance, it behaves just like a local disk—you can format it, mount it, and manage it directly through your operating system.

Cool, now, when would I use EBS?

EBS volumes are persistent, meaning your data remains intact when compute instances stop or reboot. They're ideal for workloads requiring reliable storage attached to a single compute instance. This means only one virtual machine can read from or write to the disk at any given time: there's no file sharing or network-based access across multiple machines.

Typically, Amazon EBS is used when:

• Running a **relational or NoSQL database** on a single EC2 instance.
• Hosting a monolithic application that stores files or state locally.
• Running an application server that writes, logs, caches, or stores session data to disk.
• Needing a boot volume (operating system disk) for an EC2 instance.
• Performing batch processing or machine learning training where each job runs on one node.

EBS Strengths and Weaknesses

Amazon EBS Strengths:

Amazon EBS's primary advantage is data persistence: your data remains intact even when an EC2 instance is stopped or restarted, making it ideal for stateful workloads.

It also offers tunable performance with various volume types, allowing you to independently adjust IOPS and throughput.

Additionally, you can create snapshots for backup or replication to other Availability Zones, and all volumes support encryption at rest and in transit. Most configurations, including resizing and changing volume types, can be done without downtime, providing flexibility as your storage needs evolve.

Amazon EBS Weaknesses:

The most significant limitation of EBS is that volumes can typically be attached to only one compute instance at a time. Multi-attach is available in limited situations for specific volume types and use cases.

EBS is also confined to a single Availability Zone, requiring manual snapshot creation and restoration to move data between AZs.

It doesn't natively support shared storage, making it unsuitable for workloads requiring multiple instances or user-file access.

Although performance tuning offers powerful capabilities, it demands manual monitoring and adjustments, and high-performance configurations can lead to significant cost increases.

Amazon EFS Explained: Elastic File System for Shared Storage

What is a cloud-based file system?

Unlike block storage, cloud-based file systems offer networked, shared access to files. With this approach, multiple virtual machines, containers, or services can interact simultaneously with the same directory structure. Distributed applications benefit from this collaborative architecture, as they can read from and write to a common file hierarchy in parallel.

Why is this especially valuable? Teams can share data seamlessly across compute resources without needing to implement complex synchronization mechanisms.

Amazon Elastic File System (EFS) is AWS’s fully managed network file system that delivers scalable, elastic file storage. Paired with EC2, it is ideal for situations where compute instances need to access the same files concurrently.

It supports standard **NFSv4** protocols, which is just fancy for applications being able to interact with the service as a traditional file system. No code changes or SDKs are required, plus AWS handles scaling, durability, and availability.

How to use Amazon EFS?

Once you create a file system and mount it on an EC2 instance, it behaves just like a shared directory. Applications can create, modify, or delete files using standard system calls.

Okay, so when would I use Amazon EFS over EBS?

Are you managing workloads where multiple compute instances need simultaneous file access? EFS shines in this scenario. From containerized applications to horizontally scaled web servers and distributed systems relying on shared state or configuration, EFS delivers seamless file sharing capabilities.

With its regional availability and cross-AZ mounting capabilities, EFS excels in high-availability environments. Organizations seeking consistent, low-maintenance shared file access across a distributed infrastructure will find EFS particularly valuable for mission-critical deployments.

Common use cases include:

• Multiple EC2 instances are accessing the same files concurrently.
• Running containerized workloads in ECS or EKS that need shared storage.
• Hosting web applications with shared assets.
• Maintaining centralized configuration, logs, or user home directories.

EFS Strengths and Weaknesses

Amazon EFS Strengths:

The **shared access model** stands as EFS's greatest advantage, offering full support for POSIX-compliant file operations. With this capability, coordinating workloads that need to read/write from common directories or access temporary files becomes remarkably straightforward.

What sets EFS apart is its fully elastic nature; there is no need to provision storage size in advance. As your data requirements change, the system automatically scales to accommodate.

Behind the scenes, AWS manages all aspects of scaling, replication, and availability, eliminating server management concerns. Furthermore, EFS seamlessly integrates across multiple AZs, providing built-in high availability and fault tolerance from day one.

Amazon EFS Weaknesses:

While EFS offers convenience, it brings several important tradeoffs to consider. Performance typically lags behind EBS for small, random I/O workloads due to its network-access pattern. Additionally, the cost per GB exceeds both S3 and basic EBS volumes, making it a premium option.

Regional scope presents another limitation. Though EFS can be accessed across different Availability Zones, sharing across AWS regions requires complex replication setups. Standard file access patterns are well-supported; however, EFS falls short when optimizing for high-throughput or parallel analytics workloads.

S3-Compatible Storage: A Third Category Beyond EFS and EBS

Amazon S3 has undeniably established itself as the gold standard for scalable cloud storage. With its comprehensive data management capabilities, S3 stands apart from traditional file systems. Rather than just offering basic file storage functionality, it empowers developers with an extensive API ecosystem for sophisticated data control and manipulation.

Unlike EBS and EFS, which function like traditional disk drives and network shares, S3 represents a fundamentally different approach called object storage.

S3 is:

• Stateless — no persistent connections needed
• Infinitely scalable — no capacity planning required
• Highly durable — built for 99.999999999% reliability
• Optimized for throughput — great for large data transfers

This architecture makes S3 ideal for backups, static assets, data lakes, and archives; however, it's less suitable for applications that need direct disk access with file locking, random writes, or immediate consistency.

Turning Buckets Into Volumes: The S3-Compatible Storage That Bridges the Gap

Developers love S3's scalability, durability, and vast ecosystem integration. Yet, it’s unavoidable that applications still demand a POSIX-compliant file system, not object APIs. Retrofitting those applications to work with S3 often requires refactors, new tooling, and rethinking basic I/O behavior.

Instead of redefining storage paradigms, a simpler architectural approach has emerged: combining the advantages of object storage with the convenience of local disk behavior.

These systems create a file system layer on top of S3-compatible storage, allowing applications to perform standard read/write operations just as they would with a local drive—no special API calls or code changes are required.

By bridging these paradigms, this model unlocks exciting new use cases where S3's scalability and cost-efficiency shine, while still providing the familiar interface and accessibility of a mounted file system. It enables new possibilities: streaming large datasets, training ML models, or running stateful batch jobs without requiring developers to change how their applications interact with storage.

This emerging class of storage isn't replacing EBS or EFS; S3-compatible file systems augment them. It is a complementary layer that's particularly well-suited for workloads requiring both massive scalability and lightning-fast performance, without forcing developers to choose between convenience and cost.

S3 Made Seamless: How Archil Delivers Local-Disk Speed on Cloud Object Storage

What is Archil?

Archil creates a bridge between S3 object storage and traditional file systems. It transforms S3 buckets into storage volumes that your applications can access just like local disks. This means you don't need to rewrite your code to use S3's API; your existing applications can read and write files naturally.

Designed specifically for high-performance workloads, Archil lets you leverage S3's unlimited scaling while maintaining the simplicity of standard file operations. Your applications interact with files as if they were stored locally, while Archil handles all the complexity of S3 API coordination behind the scenes.

How does Archil work?

Let’s keep it simple. Here's how Archil works:

1. Simple connection: Your EC2 instances connect to Archil via encrypted NFSv3 protocol.
2. **Seamless translation:** Archil converts your standard file operations into S3 API calls behind the scenes.

With this, Archil delivers two major advantages: **Fast reading:** When reading files, Archil streams data directly from S3 while maintaining the responsiveness of local storage.

**Efficient writing:** When writing files, Archil makes them instantly available locally while asynchronously syncing to S3 in the background.

The result? You get local disk-like performance combined with S3's unlimited scalability, without changing your application code.

Okay, when would I use S3 + Archil?

Unlike EBS, which is tightly bound to a single EC2 instance and constrained by Availability Zone boundaries, or EFS, which can suffer from latency and throughput limitations at scale, Archil provides a different approach.

It offers a globally mountable, high-speed file interface that combines the familiar feel of local storage with all the advantages of S3, including scalability, durability, and cost-effectiveness.

Great use cases for Archil include: AI/ML training at scale, cross-region or multi-zone access, analytics and query engines, or apps needing access to data lakes with millions of objects.

💡TL;DR — Use Archil when:

• Your data lives in S3, but your app expects a disk.
• EFS is too slow or costly at scale.
• EBS is too rigid or instance-bound.
• You want performance, simplicity, and scale (all at once).

Choosing Between AWS EBS, EFS, and S3 Storage Solutions

Amazon Web Services (AWS) provides a comprehensive range of storage options, each carefully designed and optimized for specific use cases and workload requirements.

When architecting your cloud infrastructure, understanding the nuanced differences between these storage solutions is essential for balancing performance, cost efficiency, and scalability.

• EBS for high-performance, single-instance workloads.
• EFS for shared file access across multiple EC2 instances.
• S3-compatible solutions like Archil when you want scalable object storage with the speed and simplicity of a local disk.

Your choice should match your workload’s performance, sharing, and scaling needs. For modern, data-heavy applications that expect fast file access, Archil bridges the gap between traditional storage and cloud-native scalability.