Reduce your array chunks number. The more chunks the more it becomes slow. code example
Example: split array in smaller arrays
const splittedArray = [];
while (originalArr.length > 0) {
splittedArray.push(originalArr.splice(0,range));
}
const splittedArray = [];
while (originalArr.length > 0) {
splittedArray.push(originalArr.splice(0,range));
}