Spring-Data-MongoDB - Updates take seconds to complete? - mongodb

Question

I am using spring data mongodb to interact with my mongodb setup. I was testing different write concerns and noticed that with Unacknowledged write concern, the time for updating 1000 documents was around 5-6 secs even though Unacknowledged write concern doesn't wait for any acknowledgement.
I tested the same with raw java driver and the time was around 40 msec.
What could be cause of this huge time difference between raw java driver and spring data mongodb update?
Note that I am using Unacknowledged write concern and mongodb v2.6.1 with default configurations.
Adding Code Used for comparison:-
Raw Java driver code:-
MongoClient mongoClient = new MongoClient("localhost", 27017);
DB db = mongoClient.getDB( "testdb" );
DBCollection collection = db.getCollection("product");
WriteResult wr = null;
try {
long start = System.currentTimeMillis();
wr = collection.update(
new BasicDBObject("productId", new BasicDBObject("$gte", 10000000)
.append("$lt", 10001000)),
new BasicDBObject("$inc", new BasicDBObject("price", 100)),
false, true, WriteConcern.UNACKNOWLEDGED);
long end = System.currentTimeMillis();
System.out.println(wr + " Time taken: " + (end - start) + " ms.");
}
Spring Code:-
Config.xml
<mongo:mongo host="localhost" port="27017" />
<mongo:db-factory dbname="testdb" mongo-ref="mongo" />
<bean id="Unacknowledged" class="com.mongodb.WriteConcern">
<constructor-arg name="w" type="int" value="0"/>
</bean>
<bean id="mongoTemplate" class="org.springframework.data.mongodb.core.MongoTemplate">
<constructor-arg name="mongoDbFactory" ref="mongoDbFactory" />
<property name="writeConcern" ref="Unacknowledged"/>
</bean>
Java Code for update function which is part of ProductDAOImpl:-
public int update(long fromProductId, long toProductId, double changeInPrice)
{
Query query = new Query(new Criteria().andOperator(
Criteria.where("productId").gte(fromProductId),
Criteria.where("productId").lt(toProductId)));
Update update = new Update().inc("price", changeInPrice);
WriteResult writeResult =
mongoTemplate.updateMulti(query, update, Product.class);
return writeResult.getN();
}
Accesing code:-
ProductDAOImpl productDAO = new ProductDAOImpl();
productDAO.setMongoTemplate(mongoTemplate);
long start = System.currentTimeMillis();
productDAO.update(10000000, 10001000, 100);
long end = System.currentTimeMillis();
System.out.println("Time taken = " + (end - start) + " ms.");
Schema:-
{
"_id" : ObjectId("53b64d000cf273a0d95a1a3d"),
"_class" : "springmongo.domain.Product",
"productId" : NumberLong(6),
"productName" : "product6",
"manufacturer" : "company30605739",
"supplier" : "supplier605739",
"category" : "category30605739",
"mfgDate" : ISODate("1968-04-26T05:00:00.881Z"),
"price" : 665689.7224373372,
"tags" : [
"tag82",
"tag61",
"tag17"
],
"reviews" : [
{
"name" : "name528965",
"rating" : 6.5
},
{
"name" : "name818975",
"rating" : 7.5
},
{
"name" : "name436239",
"rating" : 3.9
}
],
"manufacturerAdd" : {
"state" : "state55",
"country" : "country155",
"zipcode" : 718
},
"supplierAdd" : {
"state" : "state69",
"country" : "country69",
"zipcode" : 691986
}
}
Hope it helps.