<!--your preparation HTML code goes here-->
const list = new Array(1000).fill("value");
const list2 = new Array(1000).fill("value");
const list3 = new Array(1000).fill("value");
const list4 = new Array(1000).fill("value");
let i = 100;
while (i < 1000) {
list[i - 100] = list[i];
i++;
}
list.length = 900;
let i = 0;
while (i < 100) {
list2.shift();
i++;
}
list3.splice(0, 100);
list4.slice(100);
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
Move Indexes | |
Shift | |
Splice | |
Slice |
Test name | Executions per second |
---|---|
Move Indexes | 189735.0 Ops/sec |
Shift | 1124463.4 Ops/sec |
Splice | 25837784.0 Ops/sec |
Slice | 3386710.2 Ops/sec |
The benchmark defined in the provided JSON tests the performance of various methods for modifying array data in JavaScript, specifically using a few different strategies for removing elements from the beginning of an array. This is a useful performance comparison, as handling large data sets effectively can greatly impact application efficiency.
Move Indexes:
let i = 100; while (i < 1000) { list[i - 100] = list[i]; i++; } list.length = 900;
Shift:
let i = 0; while (i < 100) { list2.shift(); i++; }
shift()
method, which removes the first element from an array and reduces the array length.shift()
is generally slow for large arrays as it requires re-indexing the remaining elements after each removal.Splice:
list3.splice(0, 100);
splice()
method to remove a specified number of elements starting from a given index (in this case, the start).Slice:
list4.slice(100);
slice()
method creates a new array containing the elements from the specified start index onward. In this case, elements before the 100th index are not included in the new array.splice()
and slice()
generally perform better than shift()
as they do not involve repeated index recalculations after each operation.shift()
are more straightforward but less efficient. On the other hand, methods like "Move Indexes" may require more complex logic which can reduce code readability.In conclusion, the benchmarking results indicate the trade-offs among methods for removing elements from arrays in JavaScript, emphasizing the need for developers to select the most appropriate method based on both performance requirements and code maintainability.