context
stack-switching
| context | stack-switching | |
|---|---|---|
| 3 | 2 | |
| 280 | 102 | |
| 1.1% | 0.0% | |
| 5.7 | 10.0 | |
| 7 days ago | about 1 year ago | |
| Assembly | WebAssembly | |
| - | GNU General Public License v3.0 or later |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
context
-
Fiber in C++: Understanding the Basics
https://github.com/boostorg/context/blob/6fa6d5c50d120e69b2d...
...and this causes problems, because it can't guarantee that all fields are initialized or switched successfully: https://lists.boost.org/boost-bugs/2014/10/38476.php
Microsoft continually adds and changes fields in the TIB with each new release of Windows. Attempting to implement fibers manually is a ticking time bomb that should never be used in production.
-
History of non-standard-layout class layouts
Marginally disagree. Lots of optimization work takes advantage of knowing how the ABI works. Knowing you can pass two register returns on SysV is a particularly common optimization point. Writing context switching routines that can be reliably ported (ex, boost-context) requires this consistency of ABI. As a final example, cache locality optimizations require the ability to reason about ABI layout.
- How do you implement green threads?
stack-switching
-
WasmFX: Effect Handlers for WebAssembly
I first heard of algebraic effects in a presentation about Unison recorded at Strangeloop. Realizing that exceptions, async, generators, and continuations could all be unified and implemented on top of one language feature was mind expanding.
It looks like the juicy details are in the Explainer:
https://github.com/WebAssembly/stack-switching/blob/main/pro...
-
Fiber in C++: Understanding the Basics
"Fibers", "green threads", "stack switching", "cooperative multitasking" are essentially all the same thing, they all rely on being able to switch to a different stack within the same OS thread. As such they can be implemented either in user space or by the OS.
Only downside of the technique is that it cannot be implemented in WASM, because WASM has separate data- and call-stacks and the call stack is not accessible from within the WASM virtual machine (while 'async-await' which relies on code transformation can be implemeneted in WASM just fine).
There is a 'stack-switching proposal' for WASM though, but I don't know how what's the state of that:
https://github.com/WebAssembly/stack-switching
What are some alternatives?
ghost-userspace
marl - A hybrid thread / fiber task scheduler written in C++ 11
cgreenlet - Coroutines for C/C++
assembly - assembly projects
gruvi - Async IO for Python, Simplified
llvm-project - The LLVM Project is a collection of modular and reusable compiler and toolchain technologies.