How does docker store changes to containers only in memory without writing to disk?

  docker, question

In some circumstances, it may require a large number of newly-built docker virtual machines to be run for only a few seconds and then completely deleted, such as running unit tests and oj judgment. Under these circumstances, it is absolutely unnecessary to save the state of the virtual machine. How can docker completely store the files generated by the virtual machine in memory?

docker runThere is one--rmOptions for

--rm=false                 Automatically remove the container when it exits (incompatible with -d)