ZeroFS vs AWS EFS Benchmarks
Performance comparison conducted on AWS EC2 t3.xlarge (4 vCPUs, 16 GiB RAM) in eu-north-1 region. Results published August 2025.
Test Setup
- VM: AWS EC2 t3.xlarge, eu-north-1
- ZeroFS Storage: AWS S3 Standard
- EFS Configuration: General Purpose performance mode, Elastic throughput mode
- EFS Mount: NFS 4.1 with AWS recommended parameters
- Benchmark suite: github.com/Barre/ZeroFS/bench
- Operations per test: 10,000
Architecture Differences
ZeroFS: A single userspace process backed by S3. No other infrastructure. POSIX semantics are tested in CI with 8,662 pjdfstest cases per protocol; a few excluded cases per protocol are listed in the repo.
AWS EFS: Managed NFS service.
Performance at a Glance
Key Performance Differences
Benchmark Results
Synthetic Benchmarks
The last column states the ZeroFS figure relative to the EFS figure.
| Test | ZeroFS | AWS EFS | ZeroFS vs EFS |
|---|---|---|---|
| Sequential Writes | |||
| Operations/sec | 230.71 | 108.13 | 2.1x higher |
| Mean latency | 4.32ms | 9.22ms | 2.1x lower |
| Success rate | 100% | 100% | - |
| Data Modifications | |||
| Operations/sec | 308.60 | 181.52 | 1.7x higher |
| Mean latency | 3.23ms | 5.50ms | 1.7x lower |
| Success rate | 100% | 100% | - |
| Single File Append | |||
| Operations/sec | 300.91 | 91.11 | 3.3x higher |
| Mean latency | 3.31ms | 10.95ms | 3.3x lower |
| Success rate | 100% | 100% | - |
| Empty Files | |||
| Operations/sec | 294.87 | 195.61 | 1.5x higher |
| Mean latency | 2.74ms | 4.62ms | 1.7x lower |
| Success rate | 100% | 100% | - |
| Empty Directories | |||
| Operations/sec | 446.61 | 219.01 | 2.0x higher |
| Mean latency | 2.23ms | 4.55ms | 2.0x lower |
| Success rate | 100% | 100% | - |
| Random Reads | |||
| Operations/sec | 415.68 | 1,242.61 | 3.0x lower |
| Mean latency | 2.40ms | 0.80ms | 3.0x higher |
| Success rate | 100% | 100% | - |
Real-World Operations
| Operation | ZeroFS | AWS EFS | Notes |
|---|---|---|---|
| Git clone | 3.9s | 5.0s | ZeroFS repository |
| Cargo build | 5m 45s | 4m 56s | Development profile |
| tar -xf (ZFS source) | 40.0s | 88.1s | ZFS 2.3.3 release tarball |
Cost Analysis
Storage Cost Comparison
Based on AWS pricing in eu-north-1, as of August 2025:
AWS EFS Pricing:
- Storage: $0.30/GB-Month (Standard/SSD storage)
- Read operations: $0.03/GB transferred
- Write operations: $0.06/GB transferred
AWS S3 Standard Pricing (for ZeroFS):
- Storage: $0.023/GB-Month (first 50TB)
- EC2-to-S3 data transfer within same region: Free
- S3 API requests: billed per request, not included in the tables below
Raw Storage Cost Comparison
| Storage Size | ZeroFS (S3) Monthly | AWS EFS Monthly | Cost Difference |
|---|---|---|---|
| 100 GB | $2.30 | $30.00 | 13x more expensive |
| 1 TB | $23.00 | $300.00 | 13x more expensive |
| 10 TB | $230.00 | $3,000.00 | 13x more expensive |
| 100 TB | $2,300.00 | $30,000.00 | 13x more expensive |
Annual Storage Cost Projection
| Storage Size | ZeroFS (S3) Annual | AWS EFS Annual | Annual Difference |
|---|---|---|---|
| 100 GB | $27.60 | $360.00 | $332.40 |
| 1 TB | $276.00 | $3,600.00 | $3,324.00 |
| 10 TB | $2,760.00 | $36,000.00 | $33,240.00 |
| 100 TB | $27,600.00 | $360,000.00 | $332,400.00 |
Notes:
- ZeroFS: Primary cost is S3 storage at $0.023/GB-month. EC2-to-S3 data transfer is free within the same AWS region. S3 API request charges are not included in the tables above.
- AWS EFS: Storage is $0.30/GB-month, plus $0.03/GB for reads and $0.06/GB for writes.
- The tables above compare storage costs only. EFS's per-GB read and write charges add to the total, depending on traffic.
Key Observations
ZeroFS
- 1.5x to 3.3x higher throughput on the write and metadata tests
- 13x lower storage cost ($0.023/GB-month vs $0.30/GB-month)
- No EC2-to-S3 data transfer charges within the same AWS region
AWS EFS
- 3.0x higher throughput on random reads
- Charges $0.03/GB for reads and $0.06/GB for writes
Technical Details
Sequential Writes
Creates files in sequence. Tests metadata performance and write throughput.
ZeroFS: 10,000 files in 43.3 seconds
AWS EFS: 10,000 files in 92.5 seconds (2.1x slower)
Data Modifications
Random writes to existing files. Tests consistency and caching.
ZeroFS: 10,000 operations in 32.4 seconds
AWS EFS: 10,000 operations in 55.1 seconds (1.7x slower)
Single File Append
Appends to a single file. Tests lock contention and write ordering.
ZeroFS: 10,000 operations in 33.2 seconds
AWS EFS: 10,000 operations in 109.8 seconds (3.3x slower)
Empty File Creation
Pure metadata operations without data writes.
ZeroFS: 10,000 files in 33.9 seconds
AWS EFS: 10,000 files in 51.1 seconds (1.5x slower)
Empty Directory Creation
Tests directory metadata operations.
ZeroFS: 10,000 directories in 22.4 seconds
AWS EFS: 10,000 directories in 45.7 seconds (2.0x slower)
Random Reads
Tests read performance from various file positions.
ZeroFS: 415.68 ops/sec
AWS EFS: 1,242.61 ops/sec (3x faster)
Git Clone
Tests mixed read/write patterns with metadata operations.
ZeroFS: Completed in 3.9 seconds
AWS EFS: Completed in 5.0 seconds (1.3x slower)
Compilation Workload
Rust compilation of ZeroFS codebase. Tests mixed read/write patterns.
ZeroFS: 5 minutes 45 seconds
AWS EFS: 4 minutes 56 seconds (1.2x faster)
Archive Extraction
Extracting ZFS 2.3.3 source tarball. Tests sequential file creation with varying sizes.
ZeroFS: 40.0 seconds
AWS EFS: 88.1 seconds (2.2x slower)
Summary
On a t3.xlarge in eu-north-1, with 10,000 operations per test, ZeroFS completed the write and metadata tests 1.5x to 3.3x faster than EFS. EFS served random reads 3.0x faster.
S3 Standard storage costs $0.023/GB-month against $0.30/GB-month for EFS, and EFS adds $0.03/GB for reads and $0.06/GB for writes. For 10 TB, the storage difference alone is $33,240 per year.