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September 19, 2022

I got a mad idea, and I blame DOS week for. The background for this is special_snowflake, the FOSH computer I've been building/writing for the last 5 years. Without going into all the details (because then I'll be here for two days), its new CPU is registerless and directly reads and writes into main memory for all instructions. To make it performant, the "main memory" is 0.5-8 KiB is size and treats the actual RAM as expanded memory, copying bits of it in and out. Like a disk. Now, that leaves me with the question of organization of this expanded memory. I decided I won't go the normal route and I won't implement a virtual memory system. Which leaves me with the question of what to do.

And then it occured to me yesterday. What IF you treated your expanded memory as a literral disk and put FAT on it? To allocate memory, processes create a file of some size. Processes can pass memory objects to each other by passing filesystems paths around. All memory objects are dynamically sized. Some implementations of FAT (DR-DOS 6.0 and others) track user&group ID as well as access permissions for them. You could literally implement the well-understood-by-sysadmins Unix filesystem permissions model for all memory! Super important: a single categorization unites ALL of memory which means ALL of memory is always accounted for. Modern systems have all kinds of weird kinks. Inodes, sysfs, procfs, netlink, ioctl, device nodes, semaphores, muliple kinds of sockets, multiple namespaces for all those kinds of sockets, acl, quotas, memory maps, process trees, uids and guids, mounts, etc, etc... If you put all of those into a filesystem, you suddenly make them all observable and manipulable. Another benefit: it's now possible to dump the entire contents of memory to real disks and examine them or change them. Messing with system internals is now easier than ever! And the best part? Both the running memory and the disk image of it can be manipulated with normal filesystem tools!

This can be made to play real nice in a microkernel design with lots of system daemons offering services. I already checked the extensive Wikipedia article on FAT and I found that it practically nativelly supports being used for this purpose. You would need to repurpose some fields from what Microsoft uses them for, but this is a long and time-honoured tradition. The article (linked below) lists several mutually incompatible standards for various data structures that were all used in parallel by several operating systems from several vendors.

Besides breaking the Microsoft's non-standard on FAT, there are two other problems I can see. The first is that my CPU is big-endian and FAT is used on little-endian machines which means the multi-octet fields will be messed up. That can be lived with - this will only come into effect if somebody attempted to mount the memory image on a little-endian machine, but that can be fixed by the appropriate filesystem driver.

The much bigger problem - and the only serious problem I've so far seen - is that FAT keeps track of file contents in a singly linked list. That's.... inapropriate for quick access. :) Since the use of this scheme implies there is only one daemon which manages the memory filesystem for all other applications, and since this is the only place where file handles (or whatever) is handed out, this limitation can be worked around. The filesystem daemon could keep a special structure for all open files/assigned file handles which has a map to all clusters that are part of the file. So if you want to randomly access parts of a large file, the FS daemon doesn't have to read the entire FAT from the start, it can just read from its map. But the problem is that, since this is a memory management scheme, most files can be expected to be open. Which would mean most files would have an associated fast-access map. But then the question is why have the FAT, if most access is going through the map?

Another mitigation strategy is to take care to have the memory defragmented, and then try to assign memory in large contiguous blocks of clusters. That way, if the random access happens inside such a large block, working out the sector (=page) that is to be accessed should be straightforward. The access map cache from the previous paragraph then only needs to keep track of starts and lenghts of blocks. The scheme is simpler, requires less overhead, and should benefit from the last four decades (!) of improvements to FAT drivers and algorithms.

This manage-memory-as-a-filesystem idea can BTW also be implemented on normal registered CPUs, by having some pages (in the reserved section between the sector 0 and the first FAT table xD ) function as faux main memory for currently running processes and the rest used in the FAT.

Wikipedia page on FAT: https://en.wikipedia.org/wiki/Design_of_the_FAT_file_system

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December 12, 2025
The "With Many Eyes, All Bugs Are Shallow" Fallacy

That concept, known as "Linus's Law", is not only wrong... it's wildly wrong. Another fallacy often repeated in Open Source: "Diversity makes better software."

More from The Lunduke Journal:
https://lunduke.com/

00:14:38
December 11, 2025
LibXML2, Used by Steam, Chromium, Others is Now Abandoned

An open source library used by many of the most well known applications, including VirtualBox, GNOME, Edge, & VLC, has been officially abandoned and is now marked as "unmaintained".

More from The Lunduke Journal:
https://lunduke.com/

00:11:09
December 11, 2025
Rust in the Linux Kernel is Here to Stay

According to a reporter at the Linux Kernel Maintainer Summit, "Rust in the kernel is no longer experimental - it is now a core part of the kernel and is here to stay."

More from The Lunduke Journal:
https://lunduke.com/

00:11:07
November 22, 2023
The futility of Ad-Blockers

Ads are filling the entirety of the Web -- websites, podcasts, YouTube videos, etc. -- at an increasing rate. Prices for those ad placements are plummeting. Consumers are desperate to use ad-blockers to make the web palatable. Google (and others) are desperate to break and block ad-blockers. All of which results in... more ads and lower pay for creators.

It's a fascinatingly annoying cycle. And there's only one viable way out of it.

Looking for the Podcast RSS feed or other links? Check here:
https://lunduke.locals.com/post/4619051/lunduke-journal-link-central-tm

Give the gift of The Lunduke Journal:
https://lunduke.locals.com/post/4898317/give-the-gift-of-the-lunduke-journal

The futility of Ad-Blockers
November 21, 2023
openSUSE says "No Lunduke allowed!"

Those in power with openSUSE make it clear they will not allow me anywhere near anything related to the openSUSE project. Ever. For any reason.

Well, that settles that, then! Guess I won't be contributing to openSUSE! 🤣

Looking for the Podcast RSS feed or other links?
https://lunduke.locals.com/post/4619051/lunduke-journal-link-central-tm

Give the gift of The Lunduke Journal:
https://lunduke.locals.com/post/4898317/give-the-gift-of-the-lunduke-journal

openSUSE says "No Lunduke allowed!"
September 13, 2023
"Andreas Kling creator of Serenity OS & Ladybird Web Browser" - Lunduke’s Big Tech Show - September 13th, 2023 - Ep 044

This episode is free for all to enjoy and share.

Be sure to subscribe here at Lunduke.Locals.com to get all shows & articles (including interviews with other amazing nerds).

"Andreas Kling creator of Serenity OS & Ladybird Web Browser" - Lunduke’s Big Tech Show - September 13th, 2023 - Ep 044

[from X.com - Grummz post] Poll ... Gaming: Is It The Design That Matters?

Essentially, the the current "AAA Games" which put "everything" into Social Ideology messaging LOST. 🔥
https://x.com/Grummz/status/1999167652296818935

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December 09, 2025

#C64 I really want one of these.

December 09, 2025

For some reason videos are not processing on Locals at all. At least for me. Have two shows sitting in the "processing" queue for a full day now (with a third about to be added).

I'm talking with the Locals crew about this. Hopefully should be resolved quickly. Luckily those shows are on all of the other platforms as a backup.

December 13, 2025
Lunduke Journal Lifetime Wall 2 almost full, plus Lifetime Sub as a gift

Two quick tidbits!

First: Lifetime Wall 2 Almost Full

The 2nd Lunduke Journal Lifetime Subscriber Wall of Shame… err… I mean “Wall of Awesomeness” (which shows at the end of each video) is almost full! Holy cow! So many people have signed up over the last few days and asked to be added! Awesome!

There’s room for maybe 3 or 4 more names on there before I need to start Wall Number 3. So if you want to be on the 2nd wall, grab a Lifetime Sub quickly. (Though, really, being on the 3rd wall will be cool too.)

Plus, hey! You can snag one for $89 this month. Which is pretty sweet.

Second: Sending a Lifetime Sub as a Gift

Several of you have asked if it’s possible to send someone a Lifetime Subscription as a gift (at the discounted $89 / $99 price).

The answer is yes! And, instead of sending instructions to each of you, individually, I am including a Step-by-Step rundown on how to send someone a Lunduke Journal Lifetime Sub as a gift.

There are two options — Locals & Bitcoin — and both work equally well.

(Note: A gifted Lifetime subscription can also be applied to Substack accounts… it just can’t be purchased via Substack because of the way the system works for gifting it to another person.)

How to give a gift Lifetime Subscription via Locals:

  1. Go to Lunduke.Locals.com/support.

  2. Select “Give Once“.

  3. Enter “99“ (or more) into the amount field.

  4. Email “bryan at lunduke.com”. Include the following in that email:

    1. Have the words “Gift Sub” somewhere in the subject line.

    2. Include the email you used to make the purchase and the email address of gift recipient.

    3. Include any special instructions or requests, such as: A special message you would like included, when you would like an email sent to the recipient, or if you would prefer to let the recipient know yourself.

  5. Lunduke will send you a confirmation email after that. This usually happens within a few hours.

How to get a Lifetime Subscription with Bitcoin:

You can also send a gift Lifetime Subscription via Bitcoin.  (And it's $10 cheaper thanks to the lower processing fees of Bitcoin.)

  • Send $89 worth of Bitcoin (or more) to the following address:

bc1qyjakve8fywm8pz2v99v57yhjj0vzr2vjze6fcq

  • Email “bryan at lunduke.com”. Include the following in that email:

    1. What time you made the transaction, & how much was sent (in Bitcoin).

    2. Have the words “Gift Sub” somewhere in the subject line.

    3. Include the email address of gift recipient.

    4. Include any special instructions or requests, such as: A special message you would like included, when you would like an email sent to the recipient, or if you would prefer to let the recipient know yourself.

  • Lunduke will send you a confirmation email after that. This usually happens within a few hours.

Note: The Lifetime Subscription only applies to Substack, Locals, and the Lunduke Journal Forum. Other platforms (such as X, Patreon, & YouTube) do not provide the functionality necessary to create Lifetime Subscriptions.

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December 12, 2025
Last Week on The Lunduke Journal - Fri, Dec 12, 2025

This last week has been, as usual, a doozy for Tech News.

The Mozilla Annual Report dropped, The EU & UK ramped up their war on US Free Speech, and the future of Rust in Linux was cemented (for better or worse).

But the most widely viewed, and yelled about, story of the week — by far — was “Prisma Drops Rust for Javascript, Sees Massive Speed Increase”. I tell ya, followers of the Church of Rust get grumpy if you utter anti-Rust blasphemy!

Oh, and a quick reminder: Lifetime Subscriptions can be snagged for $89 through the end of December. Monthly & Yearly subscriptions are 50% off as well. Just because.

All Shows From the Last Week

Below are all of the shows over the last 7 days, with links to Substack (where you can get both the audio or video versions). If you want to watch on a different platform (Locals, X, Rumble, YouTube, etc.) check Lunduke.com for all of the links.

As always, thank you for making The Lunduke Journal possible. If it weren’t for your support, most of these stories would never have been told (as no other Tech News outlet is covering them).

You rule.

-Lunduke

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November 30, 2025
$89 Lifetime Subs Through Monday, Second Lifetime Wall

Holy tidal wave of subscriptions, Batman! I was not fully prepared for the flood of people taking advantage of the $89 Lifetime Sub deal!

But, hey! That’s a good thing! Welcome, new Lunduke Journal subscribers!

A few quick reminders and bits of info on this glorious Sunday:

  • The $89 Lifetime Subscription deal is good through Monday, Dec 1st. That’s tomorrow. All prices go back to normal on Tuesday.

  • For everyone who has already snagged the $89 Lifetime Sub this weekend, you will be receiving a confirmation email by sometime on Monday.

  • For every Lifetime Subscriber who wants to be added to the “Lifetime Wall” at the end of the shows (but isn’t already), toss me an email and let me know how you want your name to be displayed. I’m adding a second wall which will debut in tomorrow’s show (ran out of space on the first wall).

  • Same goes for Lifetime Subscribers who want the Lunduke Journal X account to follow your X account. Email me. Let me know what your X handle is. I’ll take it from there.

  • For the new subscribers: You can find links and details on the various perks (regardless of where you subscribe from) right here.

Monday should be fun. We’ve already got quite a few stories to cover for this week… and it’s not even Monday yet!

I took off a couple days, last week, to celebrate Thanksgiving. I figured, “There won’t be too many new stories breaking during Thanksgiving!” Boy, was I wrong!

See all of you on Monday!

-Lunduke

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