OpenAI just published this article about improving efficiency wrt to tokens: https://openai.com/index/gpt-5-6-frontier-intelligence-efficiency/ This thread has had me thinking what the impact had been during the time where I had supplied significant CI capacity to GHC. It appears that running a proper CI machine: cpu/memory/disks/networks/cooling/… end up at roughly 1MWh/ year. So for a while my own support of GHCs CI had been at 8MWh/year-10MWh/year of energy expenditure across the windows, linux and macOS builders. There is a strange dynamic in CI becoming more demanding the more capacity is available. I like to think of it along the lines: more available resources make ideas viable that haven’t been viable and thus not even considered before. The inverse of: constraints are liberating. This leads me however to a rather curious thought experiment: given the high energy cost for CI, what are the tradeoff dynamics of using LLMs to screen PRs before running CI on them? As a user of a MacBook Air, I seem to also use one of the most energy efficient computes available right now. To put this in relation, it appears to me that if I were to use a monitor with the MacBook, I’d easily double my energy consumption (e.g. a 24” Dell display), to 30-40W. And my laptop is already fairly capable of running various small models locally without much additional power drain. If we want to reduce emissions ideas like data centers in space powered by solar are rather exiting (although the delivery is has an emission problem) as are data centers powered by renewable energy source (hydro, solar, wind). In my view, the buildout of more renewable and lower emission energy is incentivized by higher energy demands (and national legislation). My family owns an electric vehicle, but the TCO wrt to emissions compare to an ICE vehicle is really complicated as we still have complex mixes of energy generation. So my mental model is: 1. Higher energy demand 2. Higher incentives for diverse energy production forms 3. Wind/Solar/… increase in efficiency and become economically more attractive over fossils energy production. 4. Reduction of emission. I have a hard time believing there are people who want energy but insist on it to be generated in a way that is high in emissions when they could equally well get the same energy for the same price emission free. In the end I’m relieved that the CI I was providing very likely was in a Datacenter that was powered by hydropower. Or so the provider at least claimed. I’m also happy that I can run small models like Gemma, Phi, … locally on my machine without internet and without relying on inference providers. I firmly believe small local models will get better over time as incentives and research will continue in that direction. Ultimately during that short time I have on this planet, I want to be for things, not against. That provides me personally with a positive outlook of what can be and come as well as joy, which I prefer over negative outlook which makes me depressed. On Thu, Jul 30, 2026 at 12:09 AM Tom Ellis via ghc-devs < ghc-devs@haskell.org> wrote:
On Wed, Jul 29, 2026 at 04:27:51PM +0000, Jaro Reinders via ghc-devs wrote:
On 7/29/26 17:21, Tom Ellis via ghc-devs 'ghc-devs at haskell.org' wrote:
"outsized relative to other life activities that the general population accepts as normal",
I think you should clarify which "general population" you mean. If you mean the general world population, I think you might be surprised with how little emissions are normal.
Some data: in 2024 total global emissions per capita were 4.73 tonnes (https://ourworldindata.org/co2-emissions). Divide that by 366 and by 24 to get 538 gCO2/h, so I think the 228 gCO2/h is quite significant if you consider the "general population". Not to mention that we have collectively agreed to bring down all our emissions to zero.
Before addressing the issues raised in your latest message, I should first check (and probably should have checked earlier) whether what you've shared in this thread is to make a case about what the GHC LLM policy should be, or whether you're sharing information that you consider of general importance, that informs your behaviour and perspective as a world citizen (and in the hope that others might consider it of importance too), but only doing so in this thread because it happened to come up in the discussion.
If the latter then I fear my response will end up with us going down an off-topic rabbit hole (albeit an interesting and important one!) but not actually contributing much insight to the topic at hand.
Tom _______________________________________________ ghc-devs mailing list -- ghc-devs@haskell.org To unsubscribe send an email to ghc-devs-leave@haskell.org