var size = 1024;
var buffer = new ArrayBuffer(size);
var bytes = new Uint8Array(buffer);
var dv = new DataView(buffer);
for (var i = 0; i < size; i++)
dv.setUint8(i, Math.ceil(Math.random() * 255));
for (var i = 0; i < size; i++)
dv.getUint8(i);
for (var i = 0; i < size; i++)
bytes[i];
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
DataView | |
Uint8Array |
Test name | Executions per second |
---|---|
DataView | 1513407.9 Ops/sec |
Uint8Array | 1317286.8 Ops/sec |
Let's break down the provided JSON data and benchmark preparation code.
Benchmark Definition
The benchmark compares two approaches to read a single byte from a buffer:
DataView
(an object that allows for direct manipulation of an ArrayBuffer)Uint8Array
(a typed array that can be used to represent an array of unsigned 8-bit integers)Test Case 1: DataView
The test case uses the following code:
for (var i = 0; i < size; i++)
dv.getUint8(i);
Here, dv
is a DataView
object created from an ArrayBuffer. The test case simply calls the getUint8()
method on the dv
object to read a single byte at each index.
Test Case 2: Uint8Array
The test case uses the following code:
for (var i = 0; i < size; i++)
bytes[i];
Here, bytes
is a Uint8Array
object created from an ArrayBuffer. The test case simply accesses each element of the array using its index.
Pros and Cons
DataView
object and perform bounds checking.Other Considerations
Math.ceil(Math.random() * 255)
. This simulates a real-world scenario where data is being read from or written to memory.Alternative Approaches
Other alternatives for reading single bytes from a buffer include:
ArrayBuffer.prototype.slice()
to create a new ArrayBuffer view and access the byte at each index.TypedArrays
or arraybuffer- viewer
that provides optimized methods for working with ArrayBuffers and typed arrays.However, these alternatives may incur additional overhead or require more complex code, so they might not be suitable for performance-critical applications.
Special JS Feature/Syntax
None are used in this benchmark. The code uses standard JavaScript features like loops, conditionals, and array access.
If you have any further questions or would like me to clarify anything, feel free to ask!