The lack of cheap reliable power is actively hurting the entire economy. This stems primarily from the fact the US coasted on the previous generation's (no pun intended) investments in the power grid. At some point you run out of your great grandparents investments into the future. Inertia doesn't last forever.
Most CPUs can address 48 bits of physical memory (hundreds of terabytes), why is that even a problem ? Is it just some hardware limitation somewhere else or badly written firmware ?
There was never a concerted effort in the PC ecosystem to force all peripherals and firmware to drop 32-bit compatibility. At some point after a decade or two of x86-64 CPUs, we should have started making GPUs that simply exposed all of their VRAM to be mapped by the host by default, instead of retaining compatibility hacks like only mapping 256MB by default. Resizable BARs should have happened at least a decade earlier, and should have been phased out by now in favor of just always mapping all the VRAM.
Even as late as the PCIe 2.0 era, it was very plausible to still have peripherals that couldn't be relied upon to support 64-bit addressing (eg. a motherboard I had back then had Firewire provided by a PCI controller behind a PCIe bridge). I'd say it was the PCIe 3.0 era when consumer PC hardware should have started making 32-bit addressing support an explicit non-goal; motherboards and peripherals should have both expected to be able to use a much wider address space to allow a GPU's entire VRAM capacity to be mapped by default. That would have been starting around the GeForce 600 and Radeon HD 7000 series 28nm GPUs circa 2012. At the very least, there should have been a push to start using Resizable BAR around then, not eight years later as actually happened. PCIe has theoretically supported 64-bit addressing from the beginning, but consumer hardware didn't start trying to actually take advantage of that in a real way until 2020.
The limits weren't always exactly 32 bits, but it was common to find that the usable address space supported by a motherboard or its chipset was at most one bit wider than necessary for fully populating its DRAM slots; ie. there wasn't physical address space to spare for a significant fraction of it to be assigned to peripherals. That meant there was continued pressure for peripherals to map only increasingly small portions of their memory into the host address space, even though the CPUs themselves usually supported physical addressing that was comfortably spacious enough.
My first desktop with DDR3 had four DIMM slots supporting 8GB modules, but the total address space was limited to 32GB including all address space used by peripherals, and the peripherals were all mapped below 4GB. So it was effectively a 35-bit system, even though Intel never shipped an x86-64 CPU with less than 36-bit physical address space and AMD never shipped less than 40-bit. Significant parts of the PC ecosystem were being stingy with address lines.
Yeah, it's the firmware. It's an AM4 board, and the BIOS only gives PCI devices the space from the top of RAM up to 512 GB. Each 32 GB BAR has to start on a 32 GB boundary, and its small doorbell BAR spills into the next slot, so each card needs 64 GB. Six won't fit. So I turn Resizable BAR off in the BIOS and resize the four R9700s from Linux, where I hit the kernel bug.
The problem is that with P2P every card will map every other card into its address space. So you're not mapping 128G but likely 512! It depends a bit on what software you use, some software is smart about this and uses a smaller sliding window if it can't use all of it at once and some software is really rigid.
Please let us know if AI patches to your firmware does anything other than brick your hardware. I'm willing to let an LLM handle a lot of things, but the firmware I need to boot is not among them.
But sites that have been doing that have existed long before LLMs and AI agents. Google Flight is a good example. You see comprehensive price comparison across different airlines, click the cheapest and book it through airline website. How is this different?
Enough people use Google flights that not being there is worse than being there. But if airlines had their way, not even that would be a available. I've looked into building my own flight search engine once, and (official) access to that data (ie not scraping) is very hard and expensive to get, to the point of being pretty much impossible if you're not a huge corporation.
This is my experience attempting to get the fastest NBA/College Basketball/NHL real time data for algorithmic trading. It was so expensive in fact, that it is better to create a custom trading application and physically attend the games.
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