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Arca Noae is modernizing OS/2 Warp for 21st century PCs

Lewis Rosenthal talks about why some companies still need to run OS/2 today – including on UEFI and GPT hardware

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Liam Proven (LP): Hello, welcome to Retro Tech Week on The Register. I am Liam Proven, the free and open source and public cloud correspondent for The Register. And with me today is Lewis Rosenthal, from Arca Noae. Lewis, hello, thanks for joining us.

Lewis Rosenthal (LR): Thanks for having me.

LP: So would you like to introduce yourself and tell us about Arca Noae and its products.

LR: Surely. I'm Lewis Rosenthal. I'm the Managing Member of Arca Noae LLC. And our flagship product is Arca OS, which is a licensed distribution of IBM's OS/2 operating system wrapped with a whole bunch of modern fixes and updates to make it viable on current hardware.

LP: That's impressive. So this is based, if I'm correct, on the the final version of OS/2 Warp, which was Warp 4?

LR: That's correct. Warp 4 or what we what we commonly call MCP 2 which was the second bundled FixPack that IBM released for Warp4. Before they merged the server kernel with the the client kernel by that point. And so the OS/2 code is latest circa 2006.

LP: Okay, and this is ultimately the sort of end result of OS/22, which came out in what 1992 I think, so that was the original 32 Bit edition of OS/22. And so it's still 32 bit operating system. Yeah. But these days, you've got support for a lot, considering all the modern technology in it. So you were telling me that it has the ability to boot on UEFI machines now, is that right?

LR: Yes. After OS 5.1, which we should be releasing very shortly, does have the ability to boot UEFI and make use of even GPT disks.

LP: That's a pretty significant technology because GPT is necessary for any hard disk of over two terabytes.

LR: That's, that's true. If you want to use more than two terabytes of space and you've got a six terabyte device, you need GPT.

LP: So, um, what is the primary audience do you think, in the 21st century?

LR: Well, there are essentially two audiences. One is established large enterprises that are still running entrenched OS/2 subsystems. We do a considerable amount of consulting for Fortune 500 companies, and they have an amazing investment in custom OS/2 software that dates back into the 1990s and the hardware on which they've been running it has aged out considerably.

Even the ability to run OS/2 Warp 4 in a virtual machine with reasonable performance has become difficult. Although running in a virtual machine is not our target environment, because we're much more excited about bare metal. We do run under VirtualBox very well. And the performance difference between Warp 4 and Arca OS under VirtualBox is palpable.

LP: I can believe that. I have run the older forerunner product, eComStation. That, as I understand it, eComStation is in a way an ancestor of Arca OS. It was sort of the the first attempt to bring OS/2 back onto the market in about early 2010 I think. And I've noticed quite a lot of interest in it on places like HackerNews in the last year – that for people who only got into this industry in the 21st century there, they've never seen this whole other family of 32-bit PC operating systems.

But it is pretty hard to get eComStation running on a modern machine today and I've been trying myself recently. It doesn't understand the notion of booting from a USB key. It can support and read USB including USB 2 but it can't boot directly off it, and it has fairly limited ability to talk to wireless networks and so on. But from what I know about Arca OS, you've managed to improve on some of that quite considerably. Is that right?

LR: We have. Our ACPI implementation is quite current. It uses the latest, the latest ACPI code and so we're able to set up the hardware when it boots in a much, much more expected fashion for the operating system.

In addition to that, we have modern networking now. We have Samba 4 for Arca OS, so there's no reason to run NetBIOS to network OS/2 systems running Arca OS – it's a considerably updated distribution. eComStation – to say that it was an ancestor would probably be an overstatement. There's not that much relation between the two distributions. When we started doing Arca OS we didn't inherit any of that code from eComStation.

We started with with Warp 4 and we just sort of took a different fork in the road. So the common thread between the two is the Warp 4 core. But beyond that Arca OS is quite different in many respects.

LP: So underneath what we're talking about is the final version of the Warp client, Warp 4, with all the later fix releases and so on for the kernel that came out of IBM, plus one big part from Warp server, I believe, which is multiprocessor support.

LR: Yes.

LP: So I mean when, when OS/2 Warp originally was current, there were multi processor PCs around, but they were not very common things. They had multiple discrete processor chips on the motherboard. In the last 15 or more years multiple cores on one socket have become common. And you've got the enablement from Warp Server running in the client kernel. And how many processes can this support, in theory?

LR: At least 32. I have a vague recollection that our limit is 64. But we haven't even tested up to 32 yet.

LP: Wow. That's that's still a huge step up, I think. I do have and I did look at Warp server when it was new, but which is more than 20 – no, it's not but it's much more than 50 years ago, um 15 years ago. But I think it could handle maybe two or four, which was a lot in the late '90s. So that's a big step up.

But I guess some limitations must remain. So it's as I understand it, it's a 32 bit operating system so it's going to handle a basic limit of four gigabytes of RAM, right?

LR: Four gigabytes of system RAM. We have limited availability of PAE memory that we can configure as a RAM disk. So if you have a system that has got 16 gigabytes of RAM in it, your theoretical maximum is four gigabytes of system memory and 12 gigabytes for a RAM disk.

Now obviously the importance of a RAM disk, or I should say the convenience of a RAM disk, has been somewhat mitigated by SSDs in the marketplace, but it's still better than just wasting 12 gigabytes of space.

LP: Yeah, absolutely.

LR: So it works well for browser cache and if you're compiling things it makes makes for good workspace.

LP: Is it doable to set the temporary directory to that RAM disk?

LR: Surely. If you are using a swap file, which is very rare that we need a swap file because with this much physical memory and systems, and you can only access four gigabytes, the need for a swap file is fairly minimal. But you could even put the swap file on the RAM disk if you wanted to.

LP: So um, I guess you know, you are constrained for now to a 32 bit kernel, but the point of that is that it keeps compatibility with all of that interesting 32 bit OS/2 software that's out there, which you're not, as I understand it, really so concerned with really open commercial market stuff. Because these things did exist – there was WordPerfect and Lotus 123 and Scribe GP and so on. But it's in-house stuff that companies have built for automating their own systems.

LR: Insofar as 32-bit OS/2 applications – yes, absolutely. We also have a robust DOS subsystem so we can... The DOS emulation in OS/2 is really top notch and Windows 3.1 – you know, it's almost funny to talk about running Windows 3.1 applications today.

But part of our market does deal with those retro computing enthusiasts who like to run older DOS and Win 3.1 software, and we can do that, especially now under UEFI, quite well.

Most of the modern systems, the CSM lacks a lot of the video BIOS emulation that is required for those sessions. But we're able to do that in UEFI for ourselves. And there will be at some point in the 5.1 or maybe 5.2 release cycle, a particular gaming-targeted release, targeted at those retro gaming enthusiasts. The performance is really really good.

LP: It is kind of strange, but the the old Win 16 platform has not completely gone away and there are still things out there which only exist in that form. Windows NT could happily run this stuff up until Windows 10 – the 32 bit edition – but no 64-bit Edition of Windows can run 16 bit code anymore, so this is a layer that Microsoft have completely discarded now, which means that going forward you're going to have the only modern OS or modern hardware that can either run this natively without emulation or something.

LR: Exactly, exactly.

LP: I hope to be talking to Jim Hall of the Free DOS project in the very near future and I looked at FreeDOS 1.3 in The Register last year. And it was very interesting to boot it in a virtual machine and see DOS recognize that it was in a virtual machine, install the driver for the VM's network card, and acquire an IP address. This is not something MS DOS used to do!

But one of the big problems the Free DOS people face is: DOS needs to talk to a BIOS, and if a computer doesn't have a BIOS, you simply cannot boot DOS on it or if you can boot it, it's then effectively like in a box – it can't talk to the display, disk.... anything. So this is something that they are looking at and experimenting with but there is no good answer for this. But that could be a quite a valuable goal actually.

People are still, you know, if you have hardware out there that absolutely requires to talk to, say, an ISO slot adapter, a VM is not going to help you here. Because, you know, if this hardware is accessed through the PC BIOS, then the VM has its own BIOS which can't see that hardware in it.

LR: Correct. Correct.

LP: So, in a way, it's almost – correct me if I'm wrong – it's almost kind of accidental that this is a product that is actually also available to the public and to hobbyists who are interested in it. That's not your primary focus, am I right?

LR: Um, well, while there are factions in management who would flip that around on the other side of the coin, I don't think when we got into developing Arca OS we were really thinking about what our real target market was going to be. But early in the process, we were contacted by a large company about doing some consulting for them. And that's sort of shifted the thinking of a couple of us at least, so it's sort of a 50/50 thing.

I mean, the important thing to remember – and sometimes we get criticized for this – that people think that we, we focus too much on our enterprise customers at the expense of our smaller home users. That's not really the case.

The enterprise customers get attention because they're larger and they need attention. And they drive development of new things. So if an enterprise customer came to us and said, "Look, we absolutely positively need a Bluetooth stack." We would work on developing a Bluetooth stack. Right now we don't have a Bluetooth stack because there isn't enough demand for it. So when the development is funded, you sort of focus on whoever's paying for the work.

But we don't want to minimize the impact of those individual users either. I mean, that's our real fan base. Because in the large companies, the large enterprises could really care less whether it's running toaster operating system or whatever. But the smaller users are really, a lot of them, OS/2 diehards... and they want to see the platform do more stuff, and we get excited about that too.

LP: I must admit, you know, I was a keen OS/2 user then myself. I've been working in this business for a long time and even back in the late '80s, when I started, it was quite common for software companies to provide evaluation copies for companies who were looking at and evaluating their product.

Not IBM! And I had to go out and buy OS/2 2.0 with my own money, which was pretty unusual even then. And I loved it. I ran it on multiple machines on 386 and 486 laptops. The slogan back then was "A better DOS than DOS, a better Windows than Windows." And it really truly was. And, you know, it's a delight to me to see that this is is still around, it's still continuing, it's a powerful capable OS. Yes, it does have some limits, but what doesn't?

And I really hope that I can get a hold of 5.1 when it comes out. I would very much like to give that a write-up. I think it's, it's going to be interesting because a lot of people tend to ask, you know, "Why would I go out and spend this money on this when when my PC came with Windows?"

Well, you know, if you're happy with what you've got, this is possibly not for you. But if you're looking for something genuinely different, and, it really was. It's a glimpse of an alternate future. And I'm really delighted to see that...

LR: One of the really sort of unsung benefits of Arca OS is that unlike some other commercial operating systems, there is absolutely no phoning home during installation or during running of the operating system.

We don't have any kind of license activation where you need to get online and activate your license so we know who you are or anything. Every ISO is personalized for each customer. And that is the extent of our copy protection, if you will. So if that ISO gets loose on the internet somewhere and we find out about it, we can trace it back to whose ISO it was. But we don't... when the system is up and running, it doesn't send any kind of telemetry back to anyone. We don't believe in that; we don't participate in any of that stuff. And there is an awful lot to be said for that in today's surveillance society.

LP: There really is, there really is. I really, really am looking forward to seeing it. Thank you very much indeed for taking the time out of your day. I really appreciated speaking to you and it has been a pleasure exchanging emails with you in the run-up to this. I look forward to seeing it, and writing about it, and trying to explain possibly to readers who weren't born yet when this kernel first came out, why it's maybe worth their time to have a look. Thank you very much indeed for your time.

LR: Thank you.

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