With some fixes, it can be pretty stable. Here's a web server running on Sprite on an IPC: https://ember.shockfox.net/
Or, well, it is running right now. I don't leave it online 24/7, so caveat emptor to future visitors.
Single system image across multiple nodes doesn't seem to be getting much mindshare either.
20 years later people are still sshing into nodes to fuss around, and treating cluster nodes like pets. it still could be done pretty easily, I guess its not really in anyone's interest to invest the 2 years it would take. there is a lot more money to be made nibbling around the edges of the problem.
Especially if you can do similarish stuff in other ways. There's several distributed filesytems available now. There's lots of process orchestration tools. Single nodes today can be enormous compared to single nodes and even some clusters from the 2000s.
but yes, right now you install all kinds of services and support nodes, and distributed filesystems, and orchestration tools and software management tools and job schedulers. every cluster is a bespoke mess that takes a large staff to maintain and is always broken.
this is kind of the projection of web software onto hpc clusters.
in the 90s it wasn't nearly as hard to run a supercomputer because it was an integrated software platform. they were still a lot dodgier than the needed to be. but you could run a 64k node system with one support person, and there weren't really very many support tickets because things just mostly worked.
but I certainly can't imagine trying to do a company that solves this problem. or I should say I keep trying to and just seeing failure. part of the issue is that the people that you are selling to are personally and monetarily invested in the status quo. I don't think they _want_ to relieved of the burden of messing around with Kubernetes all the time, and having distributed filesystems that need to be nursed all the time, or having provisioning tools that have a 80% success rate and take hours to spin up a node.
I am hoping to make a big writeup "soon", since there's a lot of interesting information about Sprite that's mostly been lost to time, where Sprite is mostly remembered as having "process migration" and "LFS". Meanwhile, it's mostly forgotten that Sprite was (apparently) one of the first OSes to adopt a mostly-GNU userland, had a modern event-loop style abstraction in C for handling I/O and timers (Fs_Dispatch), had a userspace filesystem abstraction akin to FUSE (PFS), implemented a PTY-like system entirely in userspace (the Td* functions in libc), and overcommitted memory by default.
Yep, I don't think a system for this is something you can sell by itself, unless you're selling mainframes. You'd need to be selling an application that needs the system to run.
I don't really know what kind of application really needs SSI clustering though. I've used clustering in a few different domains, but never really felt like SSI would be a clear win.
Maybe it's chicken and egg though? If SSI clustering was more available, would applications that really leveraged it arise?
The process migration + use spare capacity on the corporate network case feels potentially compelling, but only with the right kinds of workloads ... and that would be hard to sell.