From 45a7c7e822d10f67a74380198095baef28aac79e Mon Sep 17 00:00:00 2001
From: sageweil <sageweil@29311d96-e01e-0410-9327-a35deaab8ce9>
Date: Sun, 9 Sep 2007 16:10:35 +0000
Subject: [PATCH] buffer performance improvements

git-svn-id: https://ceph.svn.sf.net/svnroot/ceph@1792 29311d96-e01e-0410-9327-a35deaab8ce9
---
 trunk/ceph/include/buffer.h | 16 +++++++++++++---
 trunk/ceph/osdc/Objecter.cc |  7 ++-----
 2 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/trunk/ceph/include/buffer.h b/trunk/ceph/include/buffer.h
index 3f3650f4162e2..0e165cec82b51 100644
--- a/trunk/ceph/include/buffer.h
+++ b/trunk/ceph/include/buffer.h
@@ -338,6 +338,7 @@ public:
     bool is_page_aligned() const { return (long)c_str() % BUFFER_PAGE_SIZE == 0; }
 
     // accessors
+    raw *get_raw() const { return _raw; }
     const char *c_str() const { assert(_raw); return _raw->data + _off; }
     char *c_str() { assert(_raw); return _raw->data + _off; }
     unsigned length() const { return _len; }
@@ -729,8 +730,17 @@ public:
     }
     void append(const ptr& bp, unsigned off, unsigned len) {
       assert(len+off <= bp.length());
-      ptr tempbp(bp, off, len);
-      push_back(tempbp);
+      if (!_buffers.empty() &&
+	  _buffers.back().get_raw() == bp.get_raw() &&
+	  _buffers.back().end() == bp.start() + off) {
+	// yay contiguous with tail bp!
+	_buffers.back().set_length(_buffers.back().length()+len);
+	_len += len;
+      } else {
+	// add new item to list
+	ptr tempbp(bp, off, len);
+	push_back(tempbp);
+      }
     }
     void append(const list& bl) {
       _len += bl._len;
@@ -1108,7 +1118,7 @@ inline void _encode(const std::string& s, bufferlist& bl)
 {
   uint32_t len = s.length();
   _encoderaw(len, bl);
-  bl.append(s.c_str(), len);
+  bl.append(s.data(), len);
 }
 inline void _decode(std::string& s, bufferlist& bl, int& off)
 {
diff --git a/trunk/ceph/osdc/Objecter.cc b/trunk/ceph/osdc/Objecter.cc
index f19676a9b21fb..9d31d023ed56e 100644
--- a/trunk/ceph/osdc/Objecter.cc
+++ b/trunk/ceph/osdc/Objecter.cc
@@ -773,11 +773,8 @@ tid_t Objecter::modifyx_submit(OSDModify *wr, ObjectExtent &ex, tid_t usetid)
 	bufferlist cur;
 	for (map<size_t,size_t>::iterator bit = ex.buffer_extents.begin();
 	     bit != ex.buffer_extents.end();
-	     bit++) {
-	  bufferlist thisbit;
-	  thisbit.substr_of(((OSDWrite*)wr)->bl, bit->first, bit->second);
-	  cur.claim_append(thisbit);
-	}
+	     bit++) 
+	  ((OSDWrite*)wr)->bl.copy(bit->first, bit->second, cur);
 	assert(cur.length() == ex.length);
 	m->set_data(cur);//.claim(cur);
       }
-- 
2.39.5