This page provides a side-by-side comparison of all tools in the Azure Local Load Testing Framework. For selection guidance, see the Tool Selection Guide.
Capability Matrix
| Dimension |
fio |
iPerf3 |
HammerDB |
stress-ng |
VMFleet |
| Target OS — Linux |
✅ |
✅ |
— |
✅ |
— |
| Target OS — Windows |
— |
✅ |
✅ |
— |
✅ |
| Network testing |
— |
✅ |
— |
— |
— |
| Storage I/O testing |
✅ |
— |
— |
✅ (VFS) |
✅ |
| Database workload testing |
— |
— |
✅ |
— |
— |
| CPU stress testing |
— |
— |
— |
✅ |
— |
| Memory stress testing |
— |
— |
— |
✅ |
— |
| VM fleet workload simulation |
— |
— |
— |
— |
✅ |
| Install script included |
✅ |
— |
✅ |
— |
✅ |
| CI/CD pipeline included |
✅ |
✅ |
✅ |
✅ |
✅ |
| Ansible role included |
✅ |
— |
— |
— |
— |
Output and Metrics
| Tool |
Output Format |
Primary Metric |
Secondary Metrics |
| fio |
JSON |
IOPS |
Throughput MB/s, Latency P99 ms |
| iPerf3 |
JSON |
Throughput MB/s |
Jitter ms, Retransmits, Packet loss % |
| HammerDB |
Log → JSON |
NOPM |
TPM, Peak NOPM, Sample count |
| stress-ng |
YAML → JSON |
bogo-ops/sec |
Total bogo-ops, Real time, Usr/sys time |
| VMFleet |
CSV → JSON |
Cluster IOPS |
CPU %, Latency ms, Queue depth |
Profile Summary
| Tool |
Profile Count |
Profile Files Location |
| fio |
5 |
config/profiles/fio/ |
| iPerf3 |
3 |
config/profiles/iperf/ |
| HammerDB |
2 |
config/profiles/hammerdb/ |
| stress-ng |
3 |
config/profiles/stress-ng/ |
| VMFleet |
N/A |
config/ (config-driven, not profile-driven) |
Monitoring Coverage
| Tool |
Alert Rules |
CPU Alerts |
Memory Alerts |
Storage Alerts |
Network Alerts |
| fio |
7 |
✅ |
✅ |
✅ |
✅ |
| iPerf3 |
6 |
✅ |
✅ |
— |
✅ |
| HammerDB |
7 |
✅ |
✅ |
✅ |
✅ |
| stress-ng |
6 |
✅ |
✅ |
✅ |
— |
| VMFleet |
(shared PerfMon) |
✅ |
✅ |
✅ |
✅ |
Connectivity Requirements
| Tool |
Protocol |
Port(s) |
Auth Method |
| fio |
SSH |
TCP 22 |
Key-based (linux_ssh) |
| iPerf3 (server) |
SSH |
TCP 22 |
Key-based (linux_ssh) |
| iPerf3 (test traffic) |
TCP / UDP |
TCP/UDP 5201 |
None (direct) |
| HammerDB |
WinRM / PowerShell remoting |
TCP 5985 / 5986 |
Windows credentials (windows_winrm) |
| stress-ng |
SSH |
TCP 22 |
Key-based (linux_ssh) |
| VMFleet |
WinRM / PowerShell remoting |
TCP 5985 / 5986 |
Windows credentials (windows_winrm) |
Report Generation
All tools write an aggregate JSON file consumed by New-LoadReport.ps1. The report template and placeholder mapping differ by tool:
| Tool |
Template File |
Key Placeholders |
| fio |
reports/templates/fio-report.adoc |
{seq_read_iops}, {rand_write_iops}, {p99_latency_ms} |
| iPerf3 |
reports/templates/iperf-report.adoc |
{tcp_avg_throughput_mbps}, {udp_avg_jitter_ms} |
| HammerDB |
reports/templates/hammerdb-report.adoc |
{peak_nopm}, {avg_nopm}, {peak_tpm} |
| stress-ng |
reports/templates/stress-ng-report.adoc |
{cpu_avg_bogo_ops_per_sec}, {memory_avg_bogo_ops_per_sec} |
| VMFleet |
reports/templates/vmfleet-report.adoc |
{cluster_iops}, {avg_latency_ms} |
See the Tool Selection Guide — Combining Tools section for the recommended test sequence for production validation.