I might tell students step by step: machine code is understood and executed by a machine. -> the intel instruction to increment a register is decoded and executed by the CPU's hardware.
virtual code is understood and executed by a program that pretends to be some virtual CPU. -> a Java VM might run on an intel CPU and understand and execute Java virtual machine instructions. -> a Java VM might run on an intel VM that actually runs on an ARM CPU... -> ...like a Russian matryoshka doll, there can be any number of outer VMs before the innermost real CPU. operating systems provide protection, resource allocation, and services. most languages offer programs at least some operating system like services via a runtime service layer -> in C, this was initially "crt0" the thin c runtime -> in Go, the service layer is richer, offering thread management and goroutine multiplexing, garbage collection, and more. the Go runtime is written in Go mostly and uses C or assembler to connect to the host operating system. the Go runtime is linked with the developer's Go code, and the two of them are constitute the output of go build or go install On Tue, Sep 4, 2018 at 5:15 PM Christopher Nielsen <m4dh4t...@gmail.com> wrote: > Hi Pablo, > > Yes, that sounds like a reasonable differentiation for students. Of > course, it is more complex than that, but it's a good first principles > introduction. > > Cheers, > Chris > > > On Tue, Sep 4, 2018, 16:57 Pablo Rozas Larraondo < > p.rozas.larrao...@gmail.com> wrote: > >> Thanks for the answers. I asked this question because I'm preparing some >> tutorials to explain Go to students and I'm thinking about potential >> questions and discussions. >> >> If I understand it correctly we could say then that Go's runtime has >> things in common with a VM's runtime (I'm thinking mostly in Java's) such >> as GC, goroutine (thread) scheduling, etc. However, Go's runtime cannot be >> considered a VM because it does not compile code to an intermediate >> language, it executes compiled native code instead. >> >> Cheers, >> Pablo >> >> >> >> On Wednesday, September 5, 2018 at 3:01:52 AM UTC+10, Jake Montgomery >> wrote: >>> >>> There are a lot of differences, and for the answer to be complete, you >>> would need to specify which language you wanted to compare it to. But on a >>> really simple level, thwd's answer is more or less correct. A VM language >>> is usually compiled into an instruction set for that VM. The VM then >>> provides a lot of "special sauce." Go is (usually) compiled directly into >>> machine code to be executed directly on the target system. >>> >>> One consequence of this is that the executable can be run without having >>> any other software installed on the machine. It also means that the code >>> for the stuff you inquired about such as the garbage collector, goroutine >>> scheduling and stack management, is all present in the single executable >>> compiled by go. >>> >>> As for learning more, it depends somewhat on what your experience level >>> is, and why you want to know. If you are relatively new to programming, I >>> would recommend just using go for a while, without worrying too much about >>> the "magic." If you have a strong background already, you could start >>> learning about the stuff you mentioned. Garbage collection would be an >>> interesting place to start. I don't know of any one resource, but there are >>> a number of interesting videos (gophercon, ect) by principal architects on >>> the subject. Keep in mind that all these things are constantly evolving, so >>> any information you get may not apply to the latest version of the >>> language. >>> >>> Good luck. >>> >>> >>> >>> On Tuesday, September 4, 2018 at 10:50:03 AM UTC-4, thwd wrote: >>>> >>>> A virtual machine has its own instruction set. Go compiles to machine >>>> code for a given target (which could be a virtual machine). >>>> >>>> On Tuesday, September 4, 2018 at 12:27:49 PM UTC+2, Pablo Rozas >>>> Larraondo wrote: >>>>> >>>>> The Go documentation provides some explanation about the difference >>>>> between Go’s runtime and a virtual machine here: >>>>> >>>>> https://golang.org/doc/faq#runtime >>>>> >>>>> Does anyone can recommend a good place to learn more about this? I’d >>>>> like to better understand how Go’s garbage collector, goroutine scheduling >>>>> and stack management are handled by the runtime and how it is different >>>>> from a virtual machine. >>>>> >>>>> Thanks, >>>>> Pablo >>>>> >>>>> -- >> You received this message because you are subscribed to the Google Groups >> "golang-nuts" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to golang-nuts+unsubscr...@googlegroups.com. >> For more options, visit https://groups.google.com/d/optout. >> > -- > You received this message because you are subscribed to the Google Groups > "golang-nuts" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to golang-nuts+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- *Michael T. jonesmichael.jo...@gmail.com <michael.jo...@gmail.com>* -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. 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