Thanks Ben and John for the first feedbacks.
I also run a test on Travis CI: https://travis-ci.org/demarey/test-files-pharo-org/builds/308846128?utm_source=github_status&utm_medium=notification
Average speed difference is amazing ���
I really wonder what could be the problem. On Travis, old files.phaor.org looks to be more than 10 times faster than the server hosted at Inria ...