Issue 087: what I shipped first said the opposite of the truth

It reported "N machines run an older host than another" by comparing
versions as strings. A host reports its version as a commit, and commits
have no order. On the live mesh it named the three machines running the
NEWER host as the ones behind — ced54d4 sorts above 04a27ca and that is
all it means.

The code even carried a caveat saying versions compare as strings and that
this "is enough for the timestamps and commits this mesh uses". That was
the error, written down and not noticed: enough for timestamps, meaningless
for commits, and the mesh reports commits.

It now reports the split and claims no ordering, which is more useful as
well as more honest — the reader sees who is on which side, and that is
what decides whether a field can be sent. Ordering is left with the host,
which would have to report something ordered for anybody to have it.

This is issue 145 arriving by my own door an hour after I closed it: a
report that confidently says the opposite of the truth is worse than one
that says less.
This commit is contained in:
2026-09-30 09:29:40 +02:00
parent e10084fed6
commit a794ef9a3f
2 changed files with 44 additions and 1 deletions
@@ -2,7 +2,7 @@
status: resolved status: resolved
opened: 2026-09-22 opened: 2026-09-22
located-in: [mesh-controller internal/link/protocol.go (the report field that was missing), internal/inventory, cmd/mesh-controller (node show and status)] located-in: [mesh-controller internal/link/protocol.go (the report field that was missing), internal/inventory, cmd/mesh-controller (node show and status)]
fixed-by: mesh-controller 7683ba8 fixed-by: mesh-controller 7683ba8, corrected by 1d9c102
amended-design: amended-design:
--- ---
@@ -54,6 +54,49 @@ Two deliberate refusals to guess:
for a scheme where `10` sorts before `9`. Said in the code at the place that would have to learn, for a scheme where `10` sorts before `9`. Said in the code at the place that would have to learn,
rather than left as a surprise. rather than left as a surprise.
## What I shipped first was wrong, and the mesh said so within the hour
The first version reported *"N machine(s) run an older host than another machine does"* and worked out
which by comparing versions as strings. **A host reports its version as a commit, and commits have no
order.**
On the live mesh, with the adopted machine pushed for the first time:
```
3 machine(s) run an older host than another machine does:
g14 04a27ca
novox 04a27ca
shanks 04a27ca
```
Those three run the **newer** host — installed 09:18, against the adopted machine's 01:13. `ced54d4`
sorts above `04a27ca` and that is all it means. An arbitrary lexicographic result, presented as a fact,
about the one thing this record exists to make trustworthy.
The code carried a caveat saying versions compare as strings and that this "is enough for the timestamps
and commits this mesh uses". That was the error, written down and not noticed: it is enough for
timestamps and it is **meaningless** for commits, and the mesh reports commits.
It now reports the split and claims no ordering:
```
4 machine(s) do not all run the same host:
04a27ca g14, novox, shanks
ced54d4 ace
a host refuses a declaration carrying a field it does not know, whole — so the mesh may
send only what every one of these understands. Which of them is newer is not readable
from a commit; that needs a version the host reports as ordered
```
More useful as well as more honest — the reader sees who is on which side of the split, which is what
decides whether a field can be sent — and it leaves the ordering where it belongs: with the host, which
would have to report something ordered for anybody to have it.
**This is [issue 145](../145-a-machine-reads-healthy-while-its-modules-cannot-reach-each-other/00-report.md)
arriving by my own door**, an hour after closing it: a report that confidently says the opposite of the
truth is worse than one that says less, because it trains a reader to distrust the whole surface.
## Measured on the mesh, and one limitation it exposed ## Measured on the mesh, and one limitation it exposed
All four machines run the identical host binary — same digest, installed within eighteen seconds of each All four machines run the identical host binary — same digest, installed within eighteen seconds of each