Fwiw on the compiler front, I used to work on the msvc tool chain. It has been doing lto (aka ltcg) for a very long time at reasonably good throughput. That tool chain also has done incremental compilation on a per function basis for about 7 years. Sharing header parsing across translation units has been possible through PCH for decades. Even without PCH, inline header functions only get codegened once in ltcg mode (not counting inline expansion).
In a large multi-dll build like Windows or Office, the import/export information across modules is computed without doing codegen, so ltcg codegen can be done in parallel regardless of the module dependency graph.
I never worked deeply in the build systems for Linux based OSes or other unixes, but I gather that some symbol visibility choices make the build situation worse in Unix systems than Windows.
The first 4 years are basicaly worthless. I remember reading that the best doctors got their initial BS in engineering which has nothing to do with medicine. It simply shows they have a higher IQ than average and would have made superior doctors whether they got that engineering degree or not.
That leaves the only real difference (other than degree inflation) as being 3 years of residency, but most of the older generation of doctors effectively did the same thing entering into an existing practice or working in a hospital under an experienced physician.
If you climbed the ladder (like a lot of nurse practitioners do), the ADN+BSN took 5 years with 3-4 more years for the MSN or 4-5 years for the DNP.
Put another way, that nurse practitioner has MORE applicable years of schooling than a doctor who got some random degree with the handful of med prereqs then went to med school, internship, and residency. Lots of nurse practitioners also work in the field all the while they are in school which further increases their actual experience.
The real takeaway is that all these extra years, loans, and interest combined with fewer years to practice medicine translate into more expensive care without improving outcome.
Author here. Glad you liked it. Claude has been used to help me structure the post, but not the writing itself (except maybe proof-reading it). All the techniques I use are pretty standard tricks to retain someone's attention (in particular easily-bored students in class).
This is surprisingly apt to me. Fertilizer is apparently one of the fundamental geopolitical dependencies on capital and access to petrochemicals. Solving fertilizer would unlock a huge amount of human potential in the Global South.
Disallowing smc is a significant perf/power win. For cpus that run a large variety of large code (e.g. a web browser or ux stack), being able to cache a large instruction footprint and fetch/decode it quickly is important. Having to have the icache snoop data writes and entangle the i-fetch with the store buffer machinery would be a huge penalty to pay for a niche use case. Unlike loads, which are a small fraction of instructions to disambiguate with stores, you'd have to disambiguate every single instruction.
JIT is important to Apple platforms, and they seem to manage to make it work well enough even with the need for explicit invalidation.
FWIW if you look at WebKit/JavaScriptCore, the trend has been towards less-frequent code modification, e.g. inline caches are mostly no longer repatched inline. Whole-function reoptimization is still worth the overhead of sys_icache_invalidate() + `ISB`'ing everyone involved, but at smaller granularities not so much.
So that is only true because we do it, there is a world where we optimize differently and that self modifying version works better, reread the synthesis kernel thesis(one, it is super easy, two they did this), we could have hardware that does this. Because we don't have hardware that does this we don't
I agree with what you're saying. It's called: https://en.wikipedia.org/wiki/Object_slicing. Clearly a footgun in c++. You have to return a pointer to something that is not locally allocated.
Yes, I think it's a problem for society. Death in old age frees up social, economic, physical, and political resources for the next generation of the living. If the rich and powerful escape death, because after all they will the people with the resources to do so, society will lose the adaptability and natural change that comes from new generations taking the reins.
I think macro economics has provided significant value to society even if the model isn't precise with perfect predictions. We do have worthwhile models that the government can use to avoid making serious monetary mistakes in the face of the real business cycle. We are unlikely to trigger the awful depths of the great depression again.
The main problem I see with public economists is Goodharts law: When the predictive model becomes visible to the agents in the economy, there are stable strategies to counteract those models. So if economists want to remain good predictors of real outcomes, they have to collect massive amounts of data to feed the model but then remain mostly invisible afterward, so that the agents being analyzed don't change behavior too much.
In some sense, a known bad model that is used to set central policy may be good because the rest of the economic agents can work on a diversity of better models without correlating as much with each other and the known central model.
I don't get why the sleep deprivation continues. Seems like eliminating that would make a big difference. I have a six year old son, and since he was four it was perfectly fine for him to do his own thing for a little while if I needed a bit of extra sleep. I could see why you'd resent kids if they were constantly needy, didn't sleep, and you didn't actually enjoy their company. But for kids with typical development, this resentment maybe means that the parents aren't setting the right boundaries past age 3.
In a large multi-dll build like Windows or Office, the import/export information across modules is computed without doing codegen, so ltcg codegen can be done in parallel regardless of the module dependency graph.
I never worked deeply in the build systems for Linux based OSes or other unixes, but I gather that some symbol visibility choices make the build situation worse in Unix systems than Windows.
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