speed up docker save process

[bigdataolddriver]

the tar file generated from "docker save" is optionally keeped by the control of KEEPDIR , which I understand mostly for debugging purpose.
but even KEEPDIR =0, the tar file is always saved on disk, only deleted afterwards
I am a bit impatient and did following patch , pipe-lining with tee , to save disk IO, save time

23c23
< KEEPDIR = 1

KEEPDIR = 0
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< if KEEPDIR >= 2:
< cmd = "docker save {inp} |tee {inputfile}|tar x -f - -C {datadir}"
< sh(cmd.format(**locals()))
< else:
< cmd = "docker save {inp} |tar x -f - -C {datadir}"
< sh(cmd.format(**locals()))

---

    cmd = "docker save {inp} -o {inputfile}"
    sh(cmd.format(**locals()))
    cmd = "tar xf {inputfile} -C {datadir}"
    sh(cmd.format(**locals()))

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< # if KEEPDIR >= 2:
< # logg.warning("keeping %s", inputfile)
< # else:
< # if os.path.exists(inputfile):
< # os.remove(inputfile)

    if KEEPDIR >= 2:
        logg.warning("keeping %s", inputfile)
    else:
        if os.path.exists(inputfile):
            os.remove(inputfile)

[gdraheim]

Sorry for the late answer. You are right, the default should be to not create a saved.tar but to have the files unpacked from a pipe.

However I wanted to have it differently which took a while. So the new version of docker-edit.py can select the keep-options seperately (backed with tests now).