markbase/docs/FUSE_POC_REPORT.md

FUSE POC Test Report

Date: 2026-05-17 Environment: M4 Mac mini, macOS 26.4.1 Test Phase: Phase 1 POC Verification

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Executive Summary

Status: ✅ All tests passed

Key Findings:

• Backend detection works correctly (macOS 26.4.1 → FSKit)
• CLI commands functional (fuse detect-backend, fuse poc)
• Rust compilation successful
• Placeholder FUSE implementation ready for full implementation

Next Steps: Install FUSE-T and implement real FUSE filesystem

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Test Results

Test 1: Backend Detection

Check	Expected	Actual	Pass/Fail
macOS version detected	26.4.1	26.4.1	✅ Pass
Recommended backend	FSKit	FSKit	✅ Pass
Backend explanation	Provided	Provided	✅ Pass
Available backends listed	nfs, fskit	nfs, fskit	✅ Pass

Output:

macOS version: 26.4.1
Recommended backend: fskit
Reason: macOS 26+ supports FSKit (native, fastest)
Performance: Direct userspace path, minimal overhead

Available backends:
  nfs  - NFSv4 backend (stable, all macOS versions)
  fskit - FSKit backend (macOS 26+, fastest)

Test 2: Auto Backend Selection

Check	Expected	Actual	Pass/Fail
Backend auto-detected	FSKit	FSKit	✅ Pass
Mount path displayed	/tmp/fuse_test_auto	/tmp/fuse_test_auto	✅ Pass
macOS version shown	26.4.1	26.4.1	✅ Pass
Placeholder executed	Success	Success	✅ Pass

Test 3: Manual Backend Selection (FSKit)

Check	Expected	Actual	Pass/Fail
Backend specified	FSKit	FSKit	✅ Pass
Mount path default	/tmp/fuse_test	/tmp/fuse_test	✅ Pass
Placeholder executed	Success	Success	✅ Pass

Test 4: Manual Backend Selection (NFSv4)

Check	Expected	Actual	Pass/Fail
Backend specified	NFSv4	NFSv4	✅ Pass
Mount path default	/tmp/fuse_test	/tmp/fuse_test	✅ Pass
Placeholder executed	Success	Success	✅ Pass

Test 5: Invalid Backend Error Handling

Check	Expected	Actual	Pass/Fail
Error message shown	"Unknown backend"	"Unknown backend"	✅ Pass
Exit status	Error	Error	✅ Pass

Test 6: Compilation Check

Check	Expected	Actual	Pass/Fail
cargo check succeeds	Exit 0	Exit 0	✅ Pass
No compilation errors	True	True	✅ Pass
Warnings (acceptable)	Few warnings	4 warnings	✅ Pass

Test 7: Unit Tests

Check	Expected	Actual	Pass/Fail
cargo test fuse passes	0 failed	0 failed	✅ Pass
Backend tests	Pass	Pass	✅ Pass

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Environment Verification

Hardware

Component	Specification	Status
CPU	Apple M4 (10 cores)	✅ Verified
RAM	16 GB	✅ Verified
Storage	KIOXIA NVMe 2TB (PCIe)	✅ Verified
OS	macOS 26.4.1	✅ Verified

Software Dependencies

Dependency	Version	Status
Rust	Latest stable	✅ Verified
time crate	0.3	✅ Added
lru crate	0.12	✅ Added
libc crate	0.2	✅ Added

Downloaded Files

File	Size	Status
fuse-t-1.2.6.pkg	23 MB	✅ Downloaded
AJA_System_Test.dmg	457 KB	⚠️ Downloaded (may be HTML)

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Module Structure

Created Files:

• src/fuse/mod.rs - FUSE module entry point
• src/fuse/poc_hello.rs - Placeholder FUSE implementation
• src/fuse/backend.rs - Backend selection logic
• tests/fuse_poc_test.sh - Automated test script

Cargo.toml Updates:

• Added dependencies: time, lru, libc
• Added fuse module to lib.rs

CLI Commands Added:

• cargo run -- fuse detect-backend
• cargo run -- fuse poc --dir <path> --backend <auto|nfs|fskit>

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Backend Selection Logic

Implementation Details

pub fn select_backend() -> BackendType {
    let version = detect_macos_version();
    
    if version.starts_with("26") {
        BackendType::Fskit  // macOS 26+ supports FSKit
    } else {
        BackendType::Nfs4   // Older macOS uses NFSv4
    }
}

Test Results

macOS Version	Expected Backend	Actual Backend	Pass/Fail
26.4.1	FSKit	FSKit	✅ Pass
25.0.0 (test)	NFSv4	NFSv4	✅ Pass (unit test)

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Known Limitations

1. Placeholder Implementation: Current FUSE mount is a placeholder, not a real filesystem
2. AJA System Test: Downloaded file may be HTML page, not actual DMG
3. FUSE-T Installation: Requires sudo password (cannot auto-install)
4. Actual FUSE Library: Not yet added to dependencies (requires fuse crate)

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Next Steps

Phase 1 Completion (Requires Manual Steps)

1. Install FUSE-T:

   sudo installer -pkg ~/Downloads/fuse-t-1.2.6.pkg -target /
   

2. Verify Installation:

   ls -la /usr/local/bin/fuse-t
   fuse-t --version
   

3. Download AJA System Test Properly:

   • Visit: https://www.aja.com/en/products/aja-system-test
   • Download actual DMG file

Phase 2: Real FUSE Implementation (Day 3-5)

1. Add fuse library dependency (fuse crate)
2. Implement real FUSE operations (getattr, read, write)
3. Integrate with SQLite backend
4. Test with warren user (12,659 nodes)

Phase 3: Multi-user Concurrent Mount (Day 6-8)

1. Implement MountManager
2. Test 10 user parallel mount
3. AJA concurrent write test

Phase 4: Performance Optimization (Day 9-12)

1. Write buffering (64KB chunks)
2. LRU caching
3. FSKit backend optimization
4. 600MB/s target validation

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Test Execution Time

Test	Duration
Test 1: Backend Detection	0.3s
Test 2: Auto Backend	0.3s
Test 3: Manual FSKit	0.2s
Test 4: Manual NFSv4	0.3s
Test 5: Error Handling	0.3s
Test 6: Compilation	0.2s
Test 7: Unit Tests	0.0s
Total	1.6s

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Conclusion

Phase 1 POC Status: ✅ Successfully completed (placeholder level)

Ready for Phase 2: ✅ Yes, pending FUSE-T installation

Critical Path: Install FUSE-T → Add fuse crate → Implement real FUSE filesystem

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Generated: 2026-05-17 10:15 Test Suite Version: 1.0 Report Author: MarkBase FUSE POC Team