mongodb/jstests/mmap_v1/datasize3.js

t = db.datasize3;
t.drop();

function run(options) {
    var c = {dataSize: "test.datasize3"};
    if (options)
        Object.extend(c, options);
    return db.runCommand(c);
}

t.insert({x: 1});

a = run();
b = run({estimate: true});
printjson(t.stats());
assert.eq(a.size, b.size);

t.ensureIndex({x: 1});

for (i = 2; i < 100; i++)
    t.insert({x: i});

a = run({min: {x: 20}, max: {x: 50}}).size;
b = run({min: {x: 20}, max: {x: 50}, estimate: true}).size;

ratio = Math.min(a, b) / Math.max(a, b);

assert.lt(0.97, ratio, "sizes not equal a: " + a + " b: " + b);