A 64-Bit Raspberry Pi OS At Last

Long-term Raspberry Pi watchers will have seen a lot of OS upgrades in their time, from the first Debian Squeeze previews through the Raspbian years to the current Raspberry Pi OS. Their latest OS version is something different though, and could be one of the most important releases in the platform’s history so far, as finally there’s an official release of a 64-bit Raspberry Pi OS.

Would-be 64-bit Pi users have of course had the chance to run 64-bit GNU/Linux operating system builds from other distributions for nearly as long as there have been Pi models with 64-bit processors, but until now the official distribution has only been available as a 32-bit build. In their blog post they outline their reasons for this move in terms of compatibility and performance, and indeed we look forward to giving it a try.

Aside from being a more appropriate OS for a 64-bit Pi, this marks an interesting moment for the folks from Cambridge in that it is the first distribution that won’t run on all Pi models. Instead it requires a Pi 3 or better, which is to say the Pi 3, Zero 2 W, Pi 4, Pi 400, and the more powerful Compute Modules. All models with earlier processors including the original Pi, Pi Zero, and we think the dual-core Pi 2 require a 32-bit version, and while the Pi Zero, B+ and A+ featuring the original CPU are still in production this marks an inevitable move to 64-bit in a similar fashion to that experienced by the PC industry a decade or more ago.

As far as we know the Zero is still flying off the shelves, but this move towards an OS that will leave it behind is the expected signal that eventually there will be a Pi line-up without the original chip being present. We’re sure the 32-bit Pi will be supported for years to come, but it should be clear that the Pi’s future lies firmly in the 64-bit arena. They’ve retained their position as the board to watch oddly not by always making the most impressive hardware but by having the most well-supported operating system, and this will help them retain that advantage by ensuring that OS stays relevant.

On the subject of the future course of the Pi ship, our analysis that the Compute Module 4 is their most exciting piece of hardware still stands.

Raspberry Pi 4 Gets Its 8 Gigs

What began as a rumor becomes reality. This morning [Eben Upton] announced that the newest flavor of the Raspberry Pi 4 comes with 8 gigabytes of RAM and a sticker price of $75, roughly twice that of the base model which is now pegged at 2 GB of ram.

Originally released on June 23rd of last year, the Pi 4 came with three different options for 1, 2, or 4 GB of memory. But just a few days later, Hackaday reported on an Easter egg in the user guide that referenced an 8 GB option.

So why didn’t this version get released in 2019? That’s the crazy thing about this story. In the announcement [Eben] mentions that the Pi’s design is capable of addressing up to 16 GB of LPDDR4 SDRAM (we say bring it, but that’s a discussion for a different day). It took a year to get here because there wasn’t a source available for this 8 gig version until Micron began manufacturing the chip earlier this year.

Also addressed in this announcement is a looming changeover that was bound to happen eventually: the move from 32-bit to 64-bit operating systems on the Pi. While a 32-bit image can access all of this larger memory across multiple process, it can’t devote more than 3 GB to a single Linux process because of address space limitations. Simply put, you need more bits to access the higher addresses. Moving to a 64-bit system accomplishes that, something you can do by running unofficial builds on the Pi, but the official build didn’t support it until today’s announcement of a 64-bit beta image.

This is inevitable, not purely because of this memory limitation, but because we’ve seen examples where the juggernaut of Linux development has its own eye on a 64-bit future. Official images for Raspberry Pi have always been 32-bits, and remain so for now, but the wind is beginning to blow for this and future hardware offerings that are bumping up against limitations. Along with the news of this impending architecture switch over, the official operating system has also gotten a name change: Raspbian will henceforth be known as Raspberry Pi OS.

When [Jenny List] first reported on the 8 GB rumors last June, she speculated that today’s announcement would happen on February 29th of this year. Why the leap day? It happened to be the 8th birthday of Raspberry Pi and synced up nicely with an 8 GB surprise. Today’s announcement drops the morsel of trivia that the foundation was indeed planning on that date, but missed it by three months due to supply chain disruption associated with the coronavirus pandemic that prevented them from sourcing all the parts necessary for the new power supply design included in this revision.

We’d love to hear your thoughts on this move. Do you need 8 GB on your Pi, and does the 3 GB limitation of a 32-bit kernel matter to you? Let us know in the comments below.