I've started using SOAP UI recently to test web services and it's pretty cool, but it's a huge resource hog.
Is there any way to reduce the amount of resources it uses?
It shouldn't be a resource hog, although I've seen it do this before. I leave it running on my PC all week, and a co-worker with a similar machine (dual-core running XP) has to kill it every few hours, otherwise it keeps using CPU. I'd try uninstalling/re-installing. Currently, my instance has been up for 10 days, running a mockservice that I've been hitting very hard (I've sent it thousands of requests). CPU time total (over 10 days) is about an hour and a half, but the "right now" number is about 1%.
There are no popular alternatives, aside from writing your own client in the language of your choice.
If you're testing WCF services, you can run wcftestclient from the Visual Studio command line. It works for local or remotely hosted services. Its no good for ASMX-style .NET 2.0 SOAP services though.
if you want to test using only json, you could use some of the light weight Rest clients ex. Mozilla Rest plugin.
We test our SOAP APIs manually with SOAP UI and otherwise use jMeter for automated SOAP API testing. While having a GUI seems attractive first, I find both applications quiet user-unfriendly and time consuming to work with.
As already suggested, you could do it in code using Java or maybe use a dynamic language like Ruby:
Testing SOAP Webservices with RSpec
SOAP web Services testing in RUBY
As user mitchnull mentions in his comment:
Disabling the browser component (-Dsoapui.jxbrowser.disable=true) solved the 100% CPU usage issues for me. (when it was enabled, it periodically went to 100% CPU even when not running any tests/requests).
来源：https://stackoverflow.com/questions/6369171/improve-soap-ui-performance