Swift Using site templates
Swift recognizes an environmnet variable called $SWIFT_SITE_CONF, which points to a directory containing a swift.properties file. This swift.properties can contain multiple site definitions for the various queues available on the cluster you are using. Your local swift.properties then does not need to define the entire site. It may contain only differences you need to make that are specific to your application, like walltime.
New users are encouraged to use the configuration mechanisms described in this documentation. However, if you are migrating from an older Swift release to 0.95, the older-style configurations using sites.xml and tc.data should still work.