Can someone tell me if SQL Server Service Broker is needed for this scenario?

Question

My first ever question on stack overflow so please go easy. I have a long running windows application that continually processes sql server commands. I also have a web front end that users use occasionally use to update the same db. I've noticed that sometimes (depending on what the windows application is processing at the time) that if a user submits something to the db I receive out of memory exceptions on the server. I realise I need to dig around a bit more and optimise the code. However I cannot afford the server to go down and expect that in the future i'll be allowing more and more users on the frontend. What i really need is a system that will queue the users requests (they are not time critical) and process them when the db is ready.

I'm using SQL 2012 express.

Is SQL Service Broker the best solution, i've also looked into MSMQ.

If so can someone point me in the right direction for it would be appreciate. In my search i'm just finding a lot of things it does that i don't think i need.

Cheers

Answer 1

It depends on where you're doing the persistence work, and / or calculations. If you're doing the hard work in your Windows Application, then using a Service Broker queue won't be worthwhile, as all you will be doing is receiving a message from the Service Broker queue in your Windows Application, doing your calculations and / or queries from the Windows Application, and then persisting the results to the database: as your database is already under memory pressure, this seems like an unnecessary extra load as you could just as easily queue and retrieve the message from MSMQ (or any other queueing technology).

If however you are doing all the work in the database and your Windows Application just acts as a marshalling service - eg taking the request and palming it off to a stored procedure for actioning - then Service Broker Queues may be worth using: because they are already operating within the context of the database, they can be very efficient at persisting amd querying data.

You would also want to take into failure modes, depending on whether or not you can afford to lose any messages. To ensure message persistence in MSMQ you have to use Transactional Messaging: Service Broker is more efficient at transactional queue processing than MSMQ (because it has transaction support built in, unlike MSMQ which has to use DTC, which adds an overhead) - but if your volume of messages is low, this may not be an issue.