mon: disabled rocksdb compression when used as the backend

This significantly reduced CPU utilization on the bigbang scale
testing cluster at CERN.  Note that it is already disabled for
leveldb by default (in ceph_mon.cc).

Signed-off-by: Sage Weil <sage@redhat.com>

diff --git a/src/common/config_opts.h b/src/common/config_opts.h
index f5ea116940c53ea3954e6a6de7e89e77d8a15d73..bfaf32c164a3472f1ea9e2514316f16c7a266f49 100644 (file)
--- a/src/common/config_opts.h
+++ b/src/common/config_opts.h
@@ -764,7 +764,7 @@ OPTION(keyvaluestore_rocksdb_options, OPT_STR, "")
 // rocksdb options that will be used for omap(if omap_backend is rocksdb)
 OPTION(filestore_rocksdb_options, OPT_STR, "")
 // rocksdb options that will be used in monstore
-OPTION(mon_rocksdb_options, OPT_STR, "")
+OPTION(mon_rocksdb_options, OPT_STR, "compression=kNoCompression")
 
 /**
  * osd_*_priority adjust the relative priority of client io, recovery io,