cheerio: out of memory when using cheerio in crawler

Hi, I’m using cheerio to parse html page in a simple crawler as below, the system quickly go out of memory when processing tens of pages, my computer has more than 4GB free memory, I notice that cheerio has a load operation, do I need to unload the page explicitly or some how to let cheerio release the memory after the processing finish?

var cheerio = require('cheerio');
var request = require('request');


function parseSpecificRoom(url)
{
    request({uri: url}, function(err, resp, body) {
        var $ = cheerio.load(body);
        var price = $('.house-price').text();
        var pay = $('.pay-method').text();
        var type = $('.house-type').text().replace(/\s/g, '');
        var location = $('.xiaoqu').text().replace(/\s/g, '');
        var phone = $('.tel-num').text().replace(/\s/g, '');
        console.log(price + ', ' + pay + ', ' + type + ', ' + location + ', ' + phone)
    });
}

function parsePage(index)
{
    request({uri:'http://sz.58.com/chuzu/pn' + index}, function(err, resp, body) {
        var $ = cheerio.load(body);
        var zufang = $('#infolist').children('table').eq(1).children('tr');
        zufang.each(function(i, elem) {
            var url = $(this).children().eq(1).children().eq(0).attr('href');
            parseSpecificRoom(url)
        });
    });
}

for(var i = 1; i < 100; i++)
    parsePage(i);