I am working on a approach to performance test Point of sale application. Has anyone performance tested POS systems? If so how would the environment setup look like for performance testing? Do we need to setup multiple POS systems to simulate the required TPS or can we trigger multiple transactions from one POS system?
Basically, i am not trying to test the POS application by itself, I am trying to measure the time taken to send the request and get the response back to POS.
Thanks
Yes.
You need to specifically look at your requirements for your point of sale system and whether the focus is on the performance of the local device or the remote systems that the device connects to, either in-store or potentially across the country/internet. You also need to be very well aware of what is in your control versus what is not (such as credit card authorization times) when you start reporting on the performance of your system.
On the long question on whether you actually need to have the devices when you run a test? If the focus is the back end systems that all of the POS devices connect to, then no. You only need to exercise the interfaces of the back end systems the same way as the front end devices. Most modern systems are using a variant of standard protocols for communication so there is often a method to proxy the call to record. If not then these items can often be reconstructed from protocol analyzer (Wireshark/sniffer/...) traces or database logs containing the queries and sequence from the front end client.
if all of the requirements point to front end performance then you need really only a couple of variants on the device you are testing and the vast majority of your efforts, save for perhaps a network impairment device to slow down the network representing a congested environment, will be manual. Get your stopwatches ready.