统计 mongo 各表的 size，籍此判断是否需要做碎片整理 / 索引使用是否合理

mongo_db_size.js

/*
 * 统计 mongo 各表的 size
 *
 * zhengkai@gmail.com
 *
 * usage:
 * > mongo DB_NAME mongo_db_size.js
 */

var lCollName = [];
var iMaxLength = 0;
var iTab = 12;

var lReturn = db.getCollectionNames();
for (var i in lReturn) {
	var sName = lReturn[i];
	if (sName == 'system.indexes') {
		continue;
	}
	if (iMaxLength < sName.length) {
		iMaxLength = sName.length;
	}
	lCollName.push(sName);
}

function show(sValue, iMaxLength, bLeft) {
	if (!bLeft) {
		bLeft = false;
	}
	sValue = sValue + '';
	var sReturn = '';
	for (var i = sValue.length; i < iMaxLength; i++) {
		sReturn += ' ';
	}
	if (bLeft) {
		sReturn = sValue + sReturn;
	} else {
		sReturn += sValue;
	}
	return sReturn;
}

var sHead = show('table:', iMaxLength + 3, true);
sHead += show('size: ',  iTab);
sHead += show('index: ', iTab);
sHead += show('stroage: ', iTab);
sHead += show('s/s: ', iTab);
sHead += show('i/s: ', iTab);
print();
print(sHead);
print();

var aSum = {
	'size': 0,
	'index': 0,
	'storage': 0,
};

var sOutput = '';
for (var i in lCollName) {

	var sName = lCollName[i];
	var aStat = db.getCollection(sName).stats();

	if (!aStat.size) {
		continue;
	}

	sOutput = show(sName, iMaxLength + 3, true);
	sOutput += show((parseInt(aStat.size) / 1048576).toFixed(1) + ' MB',            iTab);
	sOutput += show((parseInt(aStat.totalIndexSize) / 1048576).toFixed(1) + ' MB',  iTab);
	sOutput += show((parseInt(aStat.storageSize) / 1048576).toFixed(1) + ' MB',     iTab);
	sOutput += show(((aStat.storageSize / aStat.size - 1) * 100).toFixed(2) + ' %', iTab);
	sOutput += show((aStat.totalIndexSize / aStat.size * 100).toFixed(2) + ' %',    iTab);

	aSum['size'] += aStat.size;
	aSum['index'] += aStat.totalIndexSize;
	aSum['storage'] += aStat.storageSize;

	print(sOutput);
}

print();
print(sHead);
print();

sOutput = show('SUM', iMaxLength + 3, true);
sOutput += show((parseInt(aSum.size) / 1048576).toFixed(1) + ' MB',       iTab);
sOutput += show((parseInt(aSum.index) / 1048576).toFixed(1) + ' MB',      iTab);
sOutput += show((parseInt(aSum.storage) / 1048576).toFixed(1) + ' MB',    iTab);
sOutput += show(((aSum.storage / aSum.size - 1) * 100).toFixed(2) + ' %', iTab);
sOutput += show((aSum.index / aSum.size * 100).toFixed(2) + ' %',         iTab);
print(sOutput);