🚀 Performance Tips

While wasp-lib adds a layer of safety and convenience, following these best practices can help you maintain high performance in your application.

1. Reuse Pointers When Possible

Allocating and freeing memory can be expensive. For operations inside a loop, it's more efficient to allocate a pointer once and reuse it.

Good

// Good: Reuse pointer for multiple operations
const arrayPtr = ArrayPointer.alloc(wasm, "double", 1000);
for (let i = 0; i < iterations; i++) {
    // Modify array data
    arrayPtr.write(newData);
    wasm._process_array(arrayPtr.ptr, 1000);
}
arrayPtr.free();

Avoid

// Avoid: Creating new pointers in loops
for (let i = 0; i < iterations; i++) {
    const arrayPtr = ArrayPointer.from(wasm, "double", 1000, newData); // Expensive
    wasm._process_array(arrayPtr.ptr, 1000);
    arrayPtr.free();
}

2. Use Appropriate Buffer Sizes

Allocate memory that is appropriately sized for your needs. Over-allocating large buffers can waste memory, while under-allocating can lead to errors.

Good

// Good: Right-sized buffer
const strPtr = StringPointer.from(wasm, input.length + 10, input); // Small overhead

Avoid

// Avoid: Oversized buffers
const strPtr = StringPointer.from(wasm, 10000, input); // Wastes memory

3. Batch Operations

Instead of transferring small chunks of data between JavaScript and WebAssembly repeatedly, batch them into larger arrays. This reduces the overhead of function calls across the JS/WASM boundary.

// Good: Process arrays in batches
const batchSize = 1000;
const arrayPtr = ArrayPointer.alloc(wasm, "float", batchSize);

for (let i = 0; i < data.length; i += batchSize) {
    const batch = data.slice(i, i + batchSize);
    arrayPtr.write(batch);
    wasm._process_batch(arrayPtr.ptr, batch.length);
}
arrayPtr.free();