On 06/04/2019 23:50, Timothy Stark wrote: > Does simh use threads to handle MP processors? I have other SIMH versions > (vaxmp and turbovax) that uses threads to take advantage of CPU cores. > > I looked through your 782 code and did not see any threads handle that vaxmp > and turbovax uses. > For the VAX 8300/8350 I just run both processors in the same thread and alternate between them on each instruction cycle. Things get a lot more complicated when threads are involved because you have to think about locking and synchronisation.
The VAX-11/782 is quite different as you actually run two separate copies of the VAX-11/780 simulator and they communicate with each other using a shared memory interconnect (simulated by shared memory on the host operating system). One VAX-11/780 runs as the master and this is the one that you interact with. It has access to all the I/O devices such as disks/tapes. The other VAX-11/780 is non-interactive and can only process workloads which are handed over from the master. This is asymmetric multiprocessing. Matt _______________________________________________ Simh mailing list Simh@trailing-edge.com http://mailman.trailing-edge.com/mailman/listinfo/simh