Le 14/01/2015 04:39, Joerg Beekmann, DeepCove Labs a écrit :
Hi
I've been exploring the possibility of hosting the Squeak/Pharo VM on MirageOS. MirageOS is a Unikernal or "Library OS" where rather than creating an executable to be run on Linux the compiler analyses dependencies right down through the device drivers and creates a kernel that can be booted on Amazon AWS EC2. http://www.openmirage.org/ http://queue.acm.org/detail.cfm?id=2566628 http://blog.acolyer.org/2015/01/13/unikernels-library-operating-systems-for-...
It seems to me that having a Smalltalk hosed in this environment would be quite useful on a number of fronts: * A simple build and deploy of Smalltalk to the cloud. The Mirage group is building unikernals from sources and then because they are small committing the entire kernel to GitHub and then pushing the kernel to AWS EC2. Web sites and APIs are an obvious application. http://amirchaudhry.com/from-jekyll-to-unikernel-in-fifty-lines/. * Smalltalk on small devices. The Mirage group is running Xen with mirage on small Intel and ARM boards. See http://openmirage.org/blog/announcing-mirage-20-release/. * These kernels can be very small, on the order of 0.25Meg for minimal HTTP servers with boot times in the ms range. A project called Jitsu https://github.com/MagnusS/jitsu modifies a DNS server to boot kernels in response to socket requests. The system making the request is unaware of the boot. * The Mirage group envisions thousands of kernels running on a single Hypervisor with his speed inter-kernel communications. See http://openmirage.org/blog/update-on-vchan. The facilitates Smalltalk systems consisting of a swarm of communicating images where each image is single threaded and concurrency is via message passing.
I've corresponded with the MirageOS group asking if they thought a language VM could be hosted on Mirage. The discussion is here: http://lists.xenproject.org/archives/html/mirageos-devel/2015-01/msg00053.ht.... Assuming we understood each other it seems the answer is "yes that should be possible".
My question is what would be involved on the Smalltalk side? I presume the effort is going to be mostly in the VM. Based on the conversation on the Mirage list I think the VM will need to be able to run a Library with an entry point called by Mirage. That seems similar to the " Embedding/VM as a DLL" project proposed here: http://www.mirandabanda.org/cogblog/cog-projects/. Is this project active? The comment indicates this is mostly refactoring & repackaging. Anyone have a perspective on this?
Best regards
Joerg
Hi, I've been thinking on that kind of question from a different point of view: cutting an application in parts, and running several single core pharo vm in different xen vms with inter domain communication (or network communication if clustered on different hosts) in order to achieve multi core processing. For ipc communication, I found libvchan , whose documentation seems to be only the xen source code and a small sample in the code, and the vicent bernadoff open mirage post (no a lot of doc) and I also found xen sockect, an older paper here http://www.researchgate.net/publication/221461399_XenSocket_A_High-Throughpu... that look interesting because it has the same api as sockets, but no more information, it seems to be only an old research paper. Forthe last one, it has been be done on top of grant table and could probably be written but I guess not trivial at all. About openmirage, since the unikernel has to deal with code dependencies, how to integrate the dependency analyser with smalltalk code in order to build a specialized vm ? And about your idea of running the vm in a dll, how will it manage primitives in specialized libraries ? I suppose you would also have to go into the dependency toolchain to describe pharo packages dependencies in terms of openmirage functionality dependencies ? May be you could also look at Android port of pharo, since it runs the vm as a jni dll ? But the primitive part of android port (libraries) do not have to deal with dependencies since android is based on linux. -- Regards, Alain