var arr = [];
var count = 10000;
for(var i = 0; i<count; i++)
{
arr.push(i);
}
var arrLen = arr.length;
var sum = 0;
for (var i = 0; i < arrLen; i++){
sum = arr[i];
}
var sum = 0;
for (var i = 0; i < arr.length; i++){
sum = arr[i];
}
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
Cache length | |
Do not cache |
Test name | Executions per second |
---|---|
Cache length | 374.6 Ops/sec |
Do not cache | 190.5 Ops/sec |
Let's break down the benchmark and its test cases.
Benchmark Overview
The benchmark measures the performance of two approaches to calculate the sum of an array:
Options Compared
The benchmark compares two options:
Pros and Cons
Caching length property:
Pros:
Cons:
Get length each time in the loop:
Pros:
Cons:
Other Considerations
Both approaches assume that the length of the array does not change during the execution of the loop. If the array is frequently resized or updated, caching the length might not be effective.
Library Usage (None)
There are no libraries used in this benchmark.
Special JS Features or Syntax (None)
There are no special JavaScript features or syntax used in this benchmark.
Alternative Benchmarks
Other alternatives to measure performance might include:
forEach()
: Compare the performance of iterating over an array using forEach()
with caching the length property versus not caching it.Keep in mind that the choice of benchmark and test cases ultimately depends on the specific use case and requirements.