Load Balancing TimeControl

Load BalancingWe’re often asked if TimeControl can be “load balanced”.  The short answer for most TimeControl clients is “You won’t need to worry about that” because the volume of traffic through TimeControl can be easily handled by a single server.  We’ve had up to 10,000 users on a single rather modestly sized TimeControl server in the past with millions and millions of timesheet lines and performance was not an issue.  However, there are some situations in very high volume situations where being able to instantly share TimeControl traffic across many servers can be valuable and TimeControl’s architecture has been able to take advantage of load-sharing since the late 1990s.

In modern-day web environments TimeControl uses Microsoft Server’s Internet Information Services (IIS) to provide the TimeControl interface to the client.  That website then communicates with the TimeControl Transaction Server which in turn talks to the database server where the TimeControl database resides.  The main bottleneck for performance in that situation is the web server itself.  It’s got a lot of work to do in order to render each page the user sees, collect the data the user submits, send that data along to the transaction server, get a response back and get the information back onto a web page that the user is looking at.

By using Microsoft’s Application Request Routing (ARR) and Network Load Balancing (NLB) which are a part of Microsoft Server, clients can use a web farm with multiple web servers serving the TimeControl sites to bypass this bottleneck.  Your IIS and Windows Server experts can configure these tools or other third party load balancers to help provide a high-volume architecture for TimeControl.  They will need to allow for “Sticky Sessions” using Client Affinity and URL Rewrites to send the data to the load balancer in order to make it work.  If ultra high availability is critical, then using Health Checking can ensure that data is instantly rerouted to healthy servers before the client even knows it.

For most clients this will never be a requirement so you likely don’t have to worry about it.  Because it’s so rare, HMS doesn’t provide services for configuring your network or your web servers so you’ll need to use your own IIS and Microsoft Server experts if this type of situation applies to you.  There are other multi-server load sharing techniques for different situations that HMS can recommend if complex architectures which might affect performance is one of your challenges.  Talk to HMS Software’s technical support team about multiple Website/TTS/ATS combinations to offload reporting or Project Management system linking.