Enterprise storage arrays from vendors like Dell EMC, NetApp, and Pure Storage are the foundation of mission-critical IT environments. Ensuring these systems deliver consistent, high performance under real-world workloads is essential for application reliability and business continuity. In this post, we’ll explore how to benchmark enterprise storage using two industry-leading tools- Fio and Vdbench– with practical configuration examples and best practices.

Why Benchmarking Enterprise Storage is Unique

Enterprise arrays are not just fast disks-they’re complex systems with:

• Multiple controllers and cache layers
• Advanced data protection (RAID, erasure coding)
• High-speed protocols (Fibre Channel, iSCSI, NVMe-oF)
• Storage tiering and virtualization
• Multi-protocol (block, file) support

Benchmarking these systems is different from testing a single SSD or HDD. You must simulate production-like workloads, test at scale, and observe performance under both normal and failure conditions.

Best Practices for Enterprise Storage Benchmarking

• Simulate real-world workloads: Use realistic mixes of random/sequential I/O, read/write ratios, and block sizes.
• Test at scale: Ensure test data sets exceed cache sizes and run with sufficient concurrency.
• Run long-duration tests: Observe steady-state performance, not just short-term cache hits.
• Monitor the full stack: Track storage, network, and server metrics.
• Document everything: Record hardware/software versions, configurations, and test parameters.
• Include failure scenarios: Simulate controller or network failures to test resilience.

Fio: Flexible I/O Tester

Fio is a versatile, scriptable tool ideal for generating a wide range of I/O workloads against enterprise storage.

Example Fio Job File for Enterprise Storage

text[global]
ioengine=libaio
direct=1
rw=randrw
rwmixread=70
bs=8k
iodepth=64
numjobs=8
size=100G
runtime=3600
time_based
group_reporting
filename=/dev/sdx   # Replace with your LUN or device

[verify]
verify=crc32

What this does:

• Simulates a 70% read/30% write random workload with 8KB blocks.
• Runs 8 parallel jobs with a queue depth of 64 for 1 hour.
• Uses direct I/O to bypass the OS cache.
• Verifies data integrity with CRC32.

Run it with:

sudo fio enterprise_test.fio

Tips:

• Use multiple devices or files to simulate multi-volume workloads.
• Adjust concurrency (numjobs, iodepth) to match your environment.
• Use --output-format=json for detailed reporting.

Vdbench: Enterprise Workload Generator

Vdbench is designed for complex, multi-host enterprise storage validation and offers granular workload definition and data validation.

Example Vdbench Configuration

text# Storage Definitions for multiple LUNs
sd=sd1,lun=/dev/sdb,size=100g,openflags=o_direct
sd=sd2,lun=/dev/sdc,size=100g,openflags=o_direct
sd=sd3,lun=/dev/sdd,size=100g,openflags=o_direct
sd=sd4,lun=/dev/sde,size=100g,openflags=o_direct

# Workload Definition: 67% read, 33% write, 8KB random
wd=wd1,sd=(sd1-sd4),xfersize=8k,rdpct=67,seekpct=100

# Run Definition: max I/O, 24 hours, 1s reporting
rd=rd1,wd=wd1,iorate=max,elapsed=86400,interval=1

Run it with:

vdbench -f enterprise_vdbench.conf

Advanced tips:

• Use the hd section to define multiple hosts for distributed testing.
• Simulate failures (e.g., disconnect a path or controller) during the run to observe failover behavior.
• Use fsd and fwd for NAS/file workloads.

Key Steps for Success

1. Profile your workload: Know your application’s I/O patterns. (capture the workload IO pattern)
2. Prepare your environment: Use dedicated test LUNs/volumes.
3. Configure your tools: Use Fio or Vdbench job files that match your workload.
4. Run and monitor: Capture storage, host, and network metrics.
5. Analyze results: Look for steady-state performance, latency spikes, and the impact of failures.
6. Document and repeat: Ensure tests are reproducible and results are transparent.

Conclusion

Benchmarking enterprise-class storage is about more than just peak numbers-it’s about understanding how your array performs under pressure, during failures, and with your real workloads. Tools like Fio and Vdbench provide the flexibility, power, and validation features needed for accurate, actionable results. By following best practices and using realistic configurations, you can ensure your storage infrastructure is ready for the demands of the modern enterprise.

References:

• SNIA Storage Performance Testing Guide
• Fio and Vdbench Official Documentation