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Container start shows a real percentage, Running only when ready
The Starting view now counts real steps, and Running appears only after a readiness check. On a cold VM that is 41 seconds with no early Running.
"Starting" on a container now shows a real percentage, and "Running" appears only when the container is ready to use. Before, the list said "Running" as soon as Docker said so. On a cold VM the terminal could still answer with an error for another minute.
Text version
The percentage rose from 0 to 99 % over 37 seconds through the steps plan, network, machine, boot, inner sandbox and readiness check. Running and 100 % appeared at 41 seconds, after the readiness check passed.
The number comes from finished steps and the progress inside the current one, such as bytes unpacked or probe attempts. It never passes the weight of the current step. If a step takes three times its usual time, the number stops and the view says so.
Running means a command runs inside the machine, the network has a gateway, the inner sandbox answers (VM with gVisor) and the file list responds. If a step fails, the view names it and offers Try again. Terminal and file view open once the container runs. Opening the terminal earlier gets "still starting" instead of an error.
Every step is timed and stored, so the weights can be taken from medians after a week of data. Details are in the documentation under Container start.