A zombie server can be detected. Detecting a zombie server can include labeling a plurality of processes as utility software, calculating a utilization of utility software on the plurality of processes executed in one or more processing resources during an interval of time, and calculating a server utilization of the one or more processing resources during the interval of time. Detecting the zombie server can also include determining whether a difference between the utilization of utility software and the server utilization is greater than a threshold, and identifying a server that hosts the processing resource as a zombie server based on a determination that the difference is smaller than the threshold.