common/options.cc: Set Filestore rocksdb compaction readahead option.

fixes: http://tracker.ceph.com/issues/21505

Signed-off-by: Mark Nelson <mnelson@redhat.com>
(cherry picked from commit 66567e573836c570040c8d8148c34b0cf9dc9ce2)

diff --git a/src/common/options.cc b/src/common/options.cc
index 4480f2ed308cdb6963693d8bd6fe64b9553daf21..de6dc10974a23da4c02e37b84a2fae18f9f8a00f 100644 (file)
--- a/src/common/options.cc
+++ b/src/common/options.cc
@@ -3650,7 +3650,7 @@ std::vector<Option> get_global_options() {
     // filestore
 
     Option("filestore_rocksdb_options", Option::TYPE_STR, Option::LEVEL_ADVANCED)
-    .set_default("")
+    .set_default("compaction_readahead_size=2097152")
     .set_description(""),
 
     Option("filestore_omap_backend", Option::TYPE_STR, Option::LEVEL_ADVANCED)