The jerasure-variant parameter is interpreted as the name of the plugin
variant to be loaded regardless of the available CPU features. The
values can be sse3, sse4, generic. It is undocumented and meant for
benchmarking purposes, primarily to force the generic plugin to be
loaded when the sse4 would be chosen.
Signed-off-by: Loic Dachary <loic@dachary.org>
Only output a message about adjusting the buffer size when it is
adjusted, not when the size does not need adjustment.
Signed-off-by: Loic Dachary <loic@dachary.org>
jerasure expects chunk sizes that are aligned on the largest possible
vector size that could be used by SSE instructions, when available (
LARGEST_VECTOR_WORDSIZE == 16 bytes ).
For techniques derived from Cauchy, encoding and decoding is done by
subdividing the chunk into packets of packetsize bytes. The operations
are done w * packetsize bytes at a time. It follows that each chunk must
have a size that is a multiple of w * packetsize bytes.
For techniques derived from Vandermonde, it is enough for a chunk to be
a multiple of w * LARGEST_VECTOR_WORDSIZE.
ErasureCodeJerasure::get_alignment returns a size alignment constraint
that has to be enforced as a multiple of the object size. The resulting
object size then has to match the chunk constraints described above
although they have no relationship with K. For Cauchy, it leads to
excessive padding, making it impossible to set sensible parameters for
when the object size is small.
When the per_chunk_alignement data member is true, the semantic of
ErasureCodeJerasure::get_alignment is changed to return a size alignment
constraint to be enforced as a multiple of the chunk size. The
ErasureCodeJerasure::get_chunk_size method is modified to use the new
semantic when appropriate.
The jerasure-per-chunk-alignement parameter is parsed to set
per_chunk_alignement for the Vandermonde and Cauchy techniques.
The memory address of a chunk is implicitly aligned to a page boundary
because it is allocated with buffer::create_page_aligned.
http://tracker.ceph.com/issues/8475Fixes: #8475
Signed-off-by: Loic Dachary <loic@dachary.org>
Enforce the restriction at initialization time, the same way it is done
for Reed Solomon. Choosing a w value different from 8,16,32 will lead to
memory corruption that cannot easily be traced to the cause.
Signed-off-by: Loic Dachary <loic@dachary.org>
This fixes a bug when the time of the OSDs and clients are not
synchronized (especially when client is ahead of OSD), and the cache
tier dirty ratio reaches the threshold, the agent skips the flush work
because it thinks the object is too young.
Signed-off-by: Zhiqiang Wang <wonzhq@hotmail.com>
The get_priv() call returns a ref; make sure we drop it if it exists.
This doesn't happen on every run because usually it is NULL and we take
the other path; it's only after the OSD has been marked down that we reach
the second path.
Signed-off-by: Sage Weil <sage@redhat.com>
When reading an object from replicated pool, ceph uses sync mode,
so it can set the results in execute_ctx correctly.
However, For the async-read in EC Pool, current code didn't set the
real results after read in complete_read_ctx.
Signed-off-by: Ma Jianpeng <jianpeng.ma@intel.com>
Give users a clue when cache pools are enabled but the hit_set is not
configured. Note that technically this will work, but not well, so for
now let's just steer them away.
Signed-off-by: Sage Weil <sage@redhat.com>
