4 ms·

I've been hoping a runtime would arise for this use case explicitly, and v8 is close. But the solution has to have multitenancy, limiting of memory and cpu, and

I've been hoping a runtime would arise for this use case explicitly, and v8 is close. But the solution has to have multitenancy, limiting of memory and cpu, and security baked in from the beginning. The lua runtime seems promising, but again, not designed for that.

hinkley 4y ago
We are going the long way around to figure out that Tannenbaum was right and we need microkernels. The IPC costs cause sticker shock, but at the end of the day perhaps they are table stakes for a provably correct system.
- doliveira 4y ago
  I was reading the Wikipedia page about this debate and I find this low-level stuff so fascinating. Wish I had done CS instead of Physics. At a low level and at a place of ignorance, I kind of wish monolithic kernels hadn't won, just like I wish the morbidly obese browsers hadn't either... They sound way more, well, sound in their theoretical basis
  - hinkley 4y ago
    There's a few clever tricks that seem to make a pretty big difference with microkernels, but I know just enough to be dangerous. I think one of the biggest ones I recall, and I think it was part of the L4 secret sauce, was the idea of throwing a number of small services into a single address space, so that a context switch requires resetting the read and write permissions, but not purging the lookup table, making context switches a couple times faster. With 64 bit addressing that gets easier, and allows other tricks. For instance recent concurrent garbage collectors in Java alias the same pages to 4(?) different addresses with different read/write permissions. Unfortunately this means your Java process can 'only' address 4 exabytes of memory instead of 16, but we will surely persevere, somehow. How that plays with Meltdown and Specter might put the kibosh on this though, and most processors don't actually support 64 bit addressing. Some only do 44, 48. That's pretty old news though. The more interesting one to me is whether there's a flavor of io_uring that could serve as the basis for a new microkernel, allowing for 'chattier' interprocess relationships to be workable by amortizing the call overhead across multiple interactions.
- db65edfc7996 4y ago
  I am still waiting for a seL4 based router, firewall, DNS server, file server, etc. Even better if we could get it into critical infrastructure (water treatment, electricity, etc). Something that is exposed to the insanity of the internet, but may not necessarily have high performance requirements. We have super computers in our pockets, we can take some performance hit if it eliminates large security concerns.
- CrazyPyroLinux 4y ago
  Something like MirageOS looks pretty cool

hinkley 4y ago

We are going the long way around to figure out that Tannenbaum was right and we need microkernels. The IPC costs cause sticker shock, but at the end of the day perhaps they are table stakes for a provably correct system.

doliveira 4y ago
I was reading the Wikipedia page about this debate and I find this low-level stuff so fascinating. Wish I had done CS instead of Physics. At a low level and at a place of ignorance, I kind of wish monolithic kernels hadn't won, just like I wish the morbidly obese browsers hadn't either... They sound way more, well, sound in their theoretical basis
- hinkley 4y ago
  There's a few clever tricks that seem to make a pretty big difference with microkernels, but I know just enough to be dangerous. I think one of the biggest ones I recall, and I think it was part of the L4 secret sauce, was the idea of throwing a number of small services into a single address space, so that a context switch requires resetting the read and write permissions, but not purging the lookup table, making context switches a couple times faster. With 64 bit addressing that gets easier, and allows other tricks. For instance recent concurrent garbage collectors in Java alias the same pages to 4(?) different addresses with different read/write permissions. Unfortunately this means your Java process can 'only' address 4 exabytes of memory instead of 16, but we will surely persevere, somehow. How that plays with Meltdown and Specter might put the kibosh on this though, and most processors don't actually support 64 bit addressing. Some only do 44, 48. That's pretty old news though. The more interesting one to me is whether there's a flavor of io_uring that could serve as the basis for a new microkernel, allowing for 'chattier' interprocess relationships to be workable by amortizing the call overhead across multiple interactions.
db65edfc7996 4y ago
I am still waiting for a seL4 based router, firewall, DNS server, file server, etc. Even better if we could get it into critical infrastructure (water treatment, electricity, etc). Something that is exposed to the insanity of the internet, but may not necessarily have high performance requirements. We have super computers in our pockets, we can take some performance hit if it eliminates large security concerns.
CrazyPyroLinux 4y ago
Something like MirageOS looks pretty cool