benchmark.js

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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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/**
 * A simple benchmark module that can be loaded
 * in order to time how many times a method executes
 * in a fixed number of seconds
 */

var benchmark = function(method, timeInMillis, args) {
    var hz,
    period,
    startTime = new Date,
    runs = 0;
    do {
    method.apply(args);
    runs++;
    totalTime = new Date - startTime;
    } while (totalTime < timeInMillis);

    // convert ms to seconds
    totalTime /= 1000;

    // period → how long per operation
    period = totalTime / runs;

    // hz → the number of operations per second
    hz = 1 / period;

    return hz;
};