Implementation Details

Namespace management, binary blob handling, partition sizing considerations, format limitations.

Multiple Namespace Support

Top-level object keys define separate namespaces. Namespace isolation allows key name collisions without conflict:

const config = {
    wifi: { ssid: "MyNetwork", password: "SecurePass" },
    mqtt: { broker: "192.168.1.100", port: 1883 },
    calibration: { temp_offset: -2.5, enabled: true }
};

const nvs = generator.generate(config, 0x6000);

Binary Blob Storage

Uint8Array values are encoded as blob entries. Blobs exceeding 8 bytes are chunked across multiple entries:

const cert = await fetch('cert.pem').then(r => r.arrayBuffer());

const config = {
    security: {
        device_cert: new Uint8Array(cert),  // ~4KB maximum
        device_id: "ESP32-001"
    }
};

const nvs = generator.generate(config, 0x6000);

Blob Size Limitations: Maximum blob size in V1 format: approximately 4000 bytes. Constraint origin: 126 entries per page, uint8 span field. For data exceeding 4KB, alternative approaches include SPIFFS storage with NVS filename references.

Partition Size Requirements

Partition sizes must be multiples of 4096 bytes. Larger partitions provide increased wear-leveling headroom at the cost of reduced usable flash capacity:

Common Partition Sizes

0x3000 (12KB)

• 3 pages, ~30-40 pairs

0x6000 (24KB)

• 6 pages, ~60-80 pairs

0x10000 (64KB)

• 16 pages, ~160-200 pairs