The parameters interpreted by the jerasure plugin are:
ceph osd erasure-code-profile set myprofile \ directory=<dir> \ # plugin directory absolute path plugin=jerasure \ # plugin name (only jerasure) k=<k> \ # data chunks (default 2) m=<m> \ # coding chunks (default 2) technique=<technique> \ # coding technique
The coding techniques can be chosen among reed_sol_van, reed_sol_r6_op, cauchy_orig, cauchy_good, liberation, blaum_roth and liber8tion.
The src/erasure-code/jerasure directory contains the implementation. It is a wrapper around the code found at https://github.com/ceph/jerasure and https://github.com/ceph/gf-complete , pinned to the latest stable version in .gitmodules. These repositories are copies of the upstream repositories http://jerasure.org/jerasure/jerasure and http://jerasure.org/jerasure/gf-complete . The difference between the two, if any, should match pull requests against upstream.