var a = new Array(100000);
for (let i=0; i<100000; i++) {
a[i] = i;
}
var b = new Set(a)
for (const x of a) {}
for (const x of b) {}
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
array | |
set |
Test name | Executions per second |
---|---|
array | 23987.3 Ops/sec |
set | 6521.1 Ops/sec |
Let's break down the provided benchmark definition and test cases.
Benchmark Definition
The benchmark is designed to compare the performance of iterating over an array versus a Set data structure in JavaScript. The script preparation code creates two large arrays and sets, each with 100,000 elements, and then assigns each element to a unique index in the array. A for...of loop is used to iterate over both the array and set.
Options Compared
Two options are compared:
for
loop with an index variable (i
) to iterate over the elements of the array.for...of
loop with a const variable (x
) to iterate over the elements of the Set data structure.Pros and Cons
Libraries Used
None
Special JS Features or Syntax
Other Considerations
When writing benchmarks, it's essential to consider factors like:
Alternatives
Other alternatives for iterating over data structures include:
Array.prototype.forEach()
or Set.prototype.forEach()
, which are more concise but may be slower than traditional loops.When interpreting benchmark results, it's crucial to consider the specific test case, data size, engine optimizations, and hardware/software overheads that may impact performance.