xoranth
Joined 10 years ago
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140
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87
Member since
Jun 26
Recent submissions
Comment · 1 year ago
Comment · 2 years ago
Are there any good how-tos for how to set up a non-trivial container with s6 and s6-rc? Last time I looked at this the documentation was pretty sparse, and more of a reference and design document than a set of how-tos.
Comment · 2 years ago
I believe they mean that since it bypasses the (Tokio) scheduler, so if you use it in async code you lose the main benefit of async code (namely, the scheduler is able to switch to some other task while waiting for IO to complete.).
Basically the same behavior you'd get if you called a blocking syscall directly.
Comment · 2 years ago
On Linux, you might be able to use userfaultfd to make it async...
Comment · 2 years ago
Thank you for your reply!
> GPUs are also just generally a lot more limiting than SIMD in many other ways.
What do you mean? (besides things like CUDA being available only on Nvidia/fragmentation issues.)
Comment · 2 years ago
Sure, but how well do they perform compared to vector loads? Do they get converted to vector load + shuffle uops, and therefore require a specific layout anyway?
Last time I tried using gathers on AVX2, performance was comparable to doing scalar loads.
Comment · 2 years ago
General questions for gamedevs here.
How useful is SIMD given that now we have compute shaders on the GPU? If so, what workloads still require SIMD/why would you choose one over the other?
Comment · 2 years ago
On x86-64, compilers use SIMD instructions and registers to implement floating point math, they just use the single lane instructions. E.g. (https://godbolt.org/z/94b3r8dMn):
float my_func(float lhs, float rhs) {
return 2.0f * lhs - 3.0f * rhs;
}
my_func(float, float):
addss xmm0, xmm0
mulss xmm1, DWORD PTR .LC0[rip]
subss xmm0, xmm1
ret
Comment · 2 years ago
Sounds a bit like Google's proposal for a `switchto_switch` syscall [1] that would allow for cooperative multithreading bypassing the scheduler.
(the descendants of that proposal is `sched_ext`, so maybe it is possible to implement doors in eBPF + sched_ext?)
Comment · 2 years ago
Thanks!
Comment · 2 years ago
Is the extension you wrote public?
Comment · 2 years ago
How would this interact with `io_uring`, especially the polling modes (IO_SETUP_SQPOLL, IO_SETUP_IOPOLL)?
Comment · 2 years ago
I believe the reason they offer no details about how they tuned the kernels is that the tuning is done by a tool provided by AMD. See here:
https://rocm.docs.amd.com/projects/rocBLAS/en/develop/how-to...
Comment · 2 years ago
Is there any good article on NT internals (that isn't Russinovich' book), that highlight where/how it is better than Linux and other *BSDs?
When asked people point to IOCP vs epoll, but I'm not sure how relevant it is now that Linux has io_uring.
(They also point to stable ABIs for drivers, but I am more interested in internals)
Can you share what LLMs do you run on such small devices/what user case they address?
(Not a rhetorical question, it's just that I see a lot of work on local inference for edge devices with small models, but I could never get a small model to work for me. So I'm curious about other people's user cases.)