4 ms·
I'm not sure this counts as "bare metal" since it runs in a VM. Though doing it this way is probably cheaper then using an FPGA.
by opwieurposiu 8y ago
I'm not sure this counts as "bare metal" since it runs in a VM. Though doing it this way is probably cheaper then using an FPGA.
- dnautics 8y agoI'm not 100% sure but I think it's not running on a VM in the virtualization sense; by VM they probably mean BEAM, which is a VM in the same sense that JVM or python are VMs.
- wiml 8y agoI was hoping they'd actually made a bare-metal BEAM implementation like the Lisp and Forth hardware that people have made in the past. This device looks like it's Erlang-on-BEAM-on-RTEMS, which is undoubtedly a more practical and useful thing, but less intriguing.
- peerst 8y agoIts not really „on RTEMS“, its more side by side. RTEMS is not a layer between the BEAM and te hardware its just helping by providing threads, TCP stack and file access. From a Erlang NIF or port driver (thats what we use to access the outside world in Erlang and Elxir) you have direct access to hardware registers and e.g. CPU interrupts.
- deleted 8y ago[deleted]
- TickleSteve 8y agoIf RTEMS is controlling the execution of your code, your running on or in RTEMS. Direct hardware access isn't really "bare metal" in the same manner as software running in DOS is not bare-metal. direct-hardware access is provided in both.
- e_proxus 8y agoRTEMS isn't "controlling" the execution of the code, it just supplies implementation for OS-specific utilities (effectively the POSIX API). The BEAM VM code is compiled to machine code and runs directly on the CPU. As peerst explained, if you write your own C code in an Erlang port driver for example, you don't have to use RTEMS at all.
- anonymousDan 8y agoIs there the ability to run multiple OS processes or is the BEAM VM the only thing running after boot?
- e_proxus 8y agoYou can only run one process in RTEMS (hence the name The Real-Time Executive for Multiprocessor Systems), however you can simulate other processes via threads. This is how we run the network stack and Wi-Fi configuration tools among other things.
- dnautics 8y agoI've always thought that erlang has a much more natural mapping onto hardware (especially multicore hardware) than lisp.
- peerst 8y agoYes we boot the BEAM on the hardware.
- deleted 8y ago[deleted]
- andrewflnr 8y agoThe distinction between an OS and a language VM is blurry. When the language VM has such robust support for concurrency and IPC, the distinction is, in terms of functionality if not name, pretty much obliterated.
- BubRoss 8y agoIt makes me wonder if anyone has made VMs using the virtualization hardware in modern computers. Nested page tables seem exceptionally useful just as a jumping off point. Maybe the fact that they would still have to use the native instruction set is the limiting factor.