osd: set erasure code packet size default to 2048

As shown in
https://www.usenix.org/legacy/events/fast09/tech/full_papers/plank/plank_html/
under "Impact of the Packet Size", the optimal for is in the order of 1k
rather than the current default of 8. Benchmarks are required to find
the actual optimum.

Signed-off-by: Loic Dachary <loic@dachary.org>

diff --git a/src/osd/ErasureCodePluginJerasure/ErasureCodeJerasure.h b/src/osd/ErasureCodePluginJerasure/ErasureCodeJerasure.h
index fc76ed7b1e21accd339cf463fede1b0a5901ae0d..a5f4c9f2476e049638ff1d9fe61b5a8d73d44543 100644 (file)
--- a/src/osd/ErasureCodePluginJerasure/ErasureCodeJerasure.h
+++ b/src/osd/ErasureCodePluginJerasure/ErasureCodeJerasure.h
@@ -125,7 +125,7 @@ public:
   static const int DEFAULT_K = 7;
   static const int DEFAULT_M = 3;
   static const int DEFAULT_W = 8;
-  static const int DEFAULT_PACKETSIZE = 8;
+  static const int DEFAULT_PACKETSIZE = 2048;
   int *bitmatrix;
   int **schedule;
   int packetsize;
@@ -177,7 +177,7 @@ public:
   static const int DEFAULT_K = 2;
   static const int DEFAULT_M = 2;
   static const int DEFAULT_W = 7;
-  static const int DEFAULT_PACKETSIZE = 8;
+  static const int DEFAULT_PACKETSIZE = 2048;
   int *bitmatrix;
   int **schedule;
   int packetsize;