``` javascript
var servers = {}
var findShard = function (id) { 
	var explain = db.random.find({_id:id}).explain();
	for (var i in explain.shards) {
		var server = explain.shards[i][0];
		if (server.n == 1) {
			if (server.server in servers) {
				servers[server.server]++;
			} else {
				servers[server.server] = 1;
			}
		}
	}
}
for (var i = 0; i <= 10000; i++) {
	var id = ObjectId();
	db.random.insert({"_id" : id, "x" : Math.random()});
	findShard(id);
}
servers
```