The request_disk attribute in HTCondor should be given in KBs:

https://htcondor.readthedocs.io/en/latest/man-pages/condor_submit.html

If a user gives a property with a postfix, for example "10 GB", Pegasus tries to do a fancy convert, like:

https://github.com/pegasus-isi/pegasus/blob/2c280c8b425f6f8afb1e4fab9b66047585d0b5ab/packages/pegasus-api/src/Pegasus/api/mixins.py#L363

However, this results in the value in the submit file being in MBs and not KBs. There might be other places in the code this conversion is broken.