def METHOD_NAME(self, bigfilename):
    c = {}
    from buildbot.config import BuilderConfig
    from buildbot.plugins import schedulers
    from buildbot.process.factory import BuildFactory
    c['schedulers'] = [
        schedulers.ForceScheduler(
            name="force",
            builderNames=["testy"])]
    f = BuildFactory()
    # do a bunch of transfer to exercise the protocol
    f.addStep(StringDownload("filecontent", workerdest="dir/file1.txt"))
    f.addStep(StringDownload("filecontent2", workerdest="dir/file2.txt"))
    # create 8 MB file
    with open(bigfilename, 'w', encoding='utf-8') as o:
        buf = "xxxxxxxx" * 1024
        for _ in range(1000):
            o.write(buf)
    f.addStep(FileDownload(mastersrc=bigfilename, workerdest="bigfile.txt"))
    f.addStep(FileUpload(workersrc="dir/file2.txt", masterdest="master.txt"))
    f.addStep(FileDownload(mastersrc="master.txt", workerdest="dir/file3.txt"))
    f.addStep(DirectoryUpload(workersrc="dir", masterdest="dir"))
    c['builders'] = [
        BuilderConfig(name="testy", workernames=["local1"], factory=f)
    ]
    yield self.setup_master(c)