A save that could not start now says so

Saving anything in the mesh works the same way underneath: read the node as it stands, work out what changed, send just that change to whoever owns the node, and wait to be told it was committed. Every answer you can get — saved, refused, denied, or "the owner never replied" — is worked out after that first read comes back.

Which left one gap, and it was the worst-behaved kind. If the connection to the node went away before that first read produced anything, the save had nothing to work from — so it never sent anything, and there was therefore nothing to be told. It did not fail. It did not succeed. It simply never answered, and it never would, because the deadline that would eventually have complained was only set once the change had been sent. Nothing appeared in the log, because as far as the system was concerned that piece of work had finished long ago.

You would notice it as a spinner that never stops, an edit that never confirms, or — most often — several things saving at once where all but one finished. That last shape is what makes it easy to mistake for something else: connections to a node are shared, so when one of several simultaneous saves tidied the shared connection away, whichever one had not yet had its first read was the one left hanging. Nine times out of ten everything is fast enough that it never happens; on a loaded machine it happens just often enough to look random.

Now that first read has to answer one way or the other. If it ends without producing the node, the save stops there and reports plainly that the change did not land and should be made again — which is the honest answer, since nothing was ever sent. Whatever was waiting on that save gets on with its life: the queue behind it moves, and anything counting saves in flight stops counting.

Two things deliberately did not change:

• A save that changes nothing still succeeds. Re-saving an unchanged page, or an edit that turns out to be identical to what is already there, completes normally without writing anything. "Nothing changed" is an outcome, not a reason to go quiet.
• Nothing waits any longer than it did. No timer was lengthened and nothing is retried. The only difference is that an outcome which previously reached nobody now reaches you.