Why does an inactive WebSphere, Version 6, server use any CPU?
Small amounts of idling CPU are usually not noticed on other platforms, because they use dedicated servers for WebSphere. But on Linux on System z where people are all sharing the same CPU, the cumulative effect of many idling WebSphere servers can be noticeable. WebSphere, Version 5, now idles at about 1 percent CPU or less, thanks to fixes made in response to concerns Linux on System z customers raised. I have seen idling WebSphere, Version 6, guests using up to 4 percent of a CPU. WebSphere, Version 6, contains many features meant to improve availability, but the features cause background threads to run, thereby increasing the CPU an idling WebSphere server uses.
