Identifying traffic patterns to web sites based on templates that characterize the arrival of traffic to the web sites is provided. Based on these templates, determinations are made as to which web sites should be co-located so as to optimize resource allocation. Web sites whose templates are complimentary, i.e. a first web site having a peak in arrival traffic at time t1 and a second web site that has a trough in arrival traffic at time t1, are designated as being candidates for co-location. In addition, the templates identified for the traffic patterns of web sites are used to determine thresholds for offloading traffic to other servers. These thresholds include a first threshold at which offloading should be performed, a second threshold that takes into consideration the lead time needed to begin offloading, and a third threshold that takes into consideration a lag time needed to stop offloading of traffic.