Threads and Interprocess Communication

7.8 Conclusion

Your design is modeled as many independent blocks running in parallel, so your testbench must also generate multiple stimulus streams and check the responses using parallel threads. These are organized into a layered testbench, orchestrated by the top-level environment. SystemVerilog introduces powerful constructs such as fork...join_none and fork...join_any for dynamically creating new threads, in addition to the standard fork...join. These threads communicate and synchronize using events, semaphore, mailboxes, and the classic @ event control and wait statement. Lastly, the disable command is used to terminate threads.

These threads and the related control constructs complement the dynamic nature of OOP. As objects are created and destroyed, they can run in independent threads, allowing you to build a powerful and flexible testbench environment.