Adding upstream version 16.2.11+ds.upstream/16.2.11+dsupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 33 insertions, 0 deletions

diff --git a/doc/dev/osd_internals/erasure_coding/jerasure.rst b/doc/dev/osd_internals/erasure_coding/jerasure.rst
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+===============
+jerasure plugin
+===============
+
+Introduction
+------------
+
+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 <https://github.com/ceph/jerasure>`_
+and `https://github.com/ceph/gf-complete
+<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
+<http://jerasure.org/jerasure/jerasure>`_ and
+`http://jerasure.org/jerasure/gf-complete
+<http://jerasure.org/jerasure/gf-complete>`_ . The difference
+between the two, if any, should match pull requests against upstream.