From a3f88918c91e6a765dd735d88ec0f03bfe5face4 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Piotr=20Da=C5=82ek?= <piotr.dalek@ts.fujitsu.com>
Date: Fri, 23 Oct 2015 15:44:47 +0200
Subject: [PATCH] os/DBObjectMap: use single-key LevelDB::get method
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Make FileStore use single-key ::get() method for some performance
increase in k/v-heavy workloads.

Signed-off-by: Piotr Dałek <piotr.dalek@ts.fujitsu.com>
---
 src/os/DBObjectMap.cc | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/src/os/DBObjectMap.cc b/src/os/DBObjectMap.cc
index 3a878ccb569..08593044b05 100644
--- a/src/os/DBObjectMap.cc
+++ b/src/os/DBObjectMap.cc
@@ -1089,17 +1089,16 @@ DBObjectMap::Header DBObjectMap::_lookup_map_header(
     }
   }
 
-  map<string, bufferlist> out;
-  set<string> to_get;
-  to_get.insert(map_header_key(oid));
-  int r = db->get(HOBJECT_TO_SEQ, to_get, &out);
-  if (r < 0 || out.empty()) {
+  bufferlist out;
+  int r = db->get(HOBJECT_TO_SEQ, map_header_key(oid), &out);
+  if (r < 0 || out.length()==0) {
     delete header;
     return Header();
   }
 
   Header ret(header, RemoveOnDelete(this));
-  bufferlist::iterator iter = out.begin()->second.begin();
+  bufferlist::iterator iter = out.begin();
+
   ret->decode(iter);
   {
     Mutex::Locker l(cache_lock);
-- 
2.47.3