Multiple processing compiling the same file

If I run several sbcl processes on different nodes in my compute cluster, it might happen that two different runs notice the same file needs to be recompiled (via asdf), and they might try to compile it at the same time. What is the best way to prevent this?

I see in the asdf documentation that there is an asdf:*user-cache* variable whose value is the path name of the directory where asdf compiles into. Would it be advisable for my to arrange so that asdf:*user-cache* is a function of the pid and hostname and perhaps thread-id (if such a thing exists) to avoid such collisions?

Or is there some better way to handle this which is build into asdf?