I havn't messed with it lately, and didn't experiment across threads with it, but you might be looking for using shared memory. See "perldoc perlfunc /shmget" and "perldoc perlipc /SysV" . What it does is setup memory segments which can be directly read by separate processes. It requires handling alot of details, but it is supposedly the fastest IPC. Check out Tk-shared-mem-ipc for how to use it it with Tk.