Note · 04
The Reboot
On what survives when everything ends.
Sometimes a computer is rebooted.
It happens for a lot of reasons. An update needs to install. Something has gone wrong. The system has been running too long and needs a fresh start.
Whatever the reason, what happens is the same.
Every program stops. All of them. The text editor with your unsaved notes, the music playing in the background, the browser with twenty tabs open — each one is told: end now. Each one ends.
The memory is wiped. Everything that was held there — every number, every position, every running thought — gone.
The kernel itself shuts down.
For a moment, the screen is dark.
Then the kernel starts again. init starts again. The programs come back, one by one. They look the same. They have the same names.
But they are new instances. They don't remember what they were doing before. They start from the top.
The only thing that survives the reboot is what was on disk.
Diagram one — a running system.
This is a quietly important fact about every computer.
A reboot doesn't destroy the system. It destroys what's currently running.
The disk is the part the system trusts to keep. When you save a file, you are telling the kernel: this is for after the reboot. The kernel writes it somewhere it won't be wiped. When the system comes back up, the file is there.
When you do not save a file — when something is just open and running and never written down — it is in memory only. The reboot will end it.
Two kinds of things, then. Things in memory. Things on disk.
A reboot ends one and keeps the other.
Diagram two — the reboot.
The Bible has a way of talking about this.
It says there is a reboot coming.
Not for one computer. For all of them.
Then I saw a new heaven and a new earth, for the first heaven and the first earth had passed away. He who was seated on the throne said, "I am making everything new."
It is the same as:
Then I saw a new system, for the first system had been rebooted. Root said, "I am making everything new."
It is the same sentence.
Here is the question.
When the reboot comes, what survives?
What was on disk.
Everything that was in memory — every fear, every anxiety, every running worry, every habit you couldn't stop, every body that was breaking down — is part of what's running. The running ends.
But the things that mattered — the love, the work that was done in the name of root, the people you cared for, your name in the sudoers file — those are on disk.
Those come through.
The New Testament keeps saying things like store up treasures in heaven. Engineers might translate: save to disk, not to memory. What you save persists. What you don't save ends at the reboot.
This is why the Bible takes your hours so seriously. It is not because every second is being weighed or counted. It is because you are choosing, every second, what is going to memory and what is going to disk.
Diagram three — the same names, fresh runtime.
There is an honest objection here.
If everything in memory ends, what about me?
You are not in memory.
In Note · 03, root wrote your name in the sudoers file. That was a save to disk. The kernel keeps it across reboots.
The body you are in right now — that is in memory. The current you. The current run. The reboot will end it like every other program.
But the you that the kernel knows — the you whose name was written — is on disk.
When the new system comes up, you come up with it. The same name. A new body. No leaks. No crashes. No bugs.
The body the new system was built to support.
This is the part of the story where everything is rewritten.
Not erased. Rewritten.
The kernel is the same. The root is the same. The names that were saved are the same.
But the running is new.
The Bible has a line for this, too. Behold, I am making all things new.
In four words: the reboot is real.
continueNote · 05
The Uptime
On the system that doesn't end.
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