From 97562e100ee757c5e5c87902acf57f3d5bdaefd7 Mon Sep 17 00:00:00 2001
From: simon gao <simon29rock@gmail.com>
Date: Wed, 13 Nov 2019 05:51:07 -0500
Subject: [PATCH] mds: optimize function, fragset_t::simplify, to improve the
 efficiency of  merging fragment

Signed-off-by: simon gao <simon29rock@gmail.com>
---
 src/include/frag.h  | 39 +++++++++++++++++++++------------------
 src/mds/MDCache.cc  |  7 ++++---
 src/mds/Migrator.cc |  4 ++--
 3 files changed, 27 insertions(+), 23 deletions(-)

diff --git a/src/include/frag.h b/src/include/frag.h
index 5e8b154f12fa1..de532d63af447 100644
--- a/src/include/frag.h
+++ b/src/include/frag.h
@@ -159,7 +159,13 @@ public:
     decode_raw(v, p);
     _enc = v;
   }
-
+  bool operator<(const frag_t& b) const
+  {
+    if (value() != b.value())
+      return value() < b.value();
+    else
+      return bits() < b.bits();
+  }
 private:
   _frag_t _enc = 0;
 };
@@ -546,7 +552,6 @@ inline std::ostream& operator<<(std::ostream& out, const fragtree_t& ft)
   return out << ")";
 }
 
-
 /**
  * fragset_t -- a set of fragments
  */
@@ -567,29 +572,27 @@ public:
       f = f.parent();
     }
   }
-  
+
+  void insert_raw(frag_t f){
+    _set.insert(f);
+  }
   void insert(frag_t f) {
     _set.insert(f);
     simplify();
   }
 
   void simplify() {
-    while (1) {
-      bool clean = true;
-      std::set<frag_t>::iterator p = _set.begin();
-      while (p != _set.end()) {
-	if (!p->is_root() &&
-	    _set.count(p->get_sibling())) {
-	  _set.erase(p->get_sibling());
-	  _set.insert(p->parent());
-	  _set.erase(p++);
-	  clean = false;
-	} else {
-	  p++;
-	}
+    auto it = _set.begin();
+    while (it != _set.end()) {
+      if (!it->is_root() &&
+	  _set.count(it->get_sibling())) {
+	_set.erase(it->get_sibling());
+	auto ret = _set.insert(it->parent());
+	_set.erase(it);
+	it = ret.first;
+      } else {
+	++it;
       }
-      if (clean)
-	break;
     }
   }
 };
diff --git a/src/mds/MDCache.cc b/src/mds/MDCache.cc
index 41d0411352a1b..0e54d2740b3e8 100644
--- a/src/mds/MDCache.cc
+++ b/src/mds/MDCache.cc
@@ -1129,11 +1129,12 @@ void MDCache::get_force_dirfrag_bound_set(const vector<dirfrag_t>& dfs, set<CDir
   // sort by ino
   map<inodeno_t, fragset_t> byino;
   for (auto& frag : dfs) {
-    byino[frag.ino].insert(frag.frag);
+    byino[frag.ino].insert_raw(frag.frag);
   }
   dout(10) << " by ino: " << byino << dendl;
 
   for (map<inodeno_t,fragset_t>::iterator p = byino.begin(); p != byino.end(); ++p) {
+    p->second.simplify();
     CInode *diri = get_inode(p->first);
     if (!diri)
       continue;
@@ -1190,13 +1191,13 @@ void MDCache::map_dirfrag_set(const list<dirfrag_t>& dfs, set<CDir*>& result)
   // group by inode
   map<inodeno_t, fragset_t> ino_fragset;
   for (const auto &df : dfs) {
-    ino_fragset[df.ino].insert(df.frag);
+    ino_fragset[df.ino].insert_raw(df.frag);
   }
-
   // get frags
   for (map<inodeno_t, fragset_t>::iterator p = ino_fragset.begin();
        p != ino_fragset.end();
        ++p) {
+    p->second.simplify();
     CInode *in = get_inode(p->first);
     if (!in)
       continue;
diff --git a/src/mds/Migrator.cc b/src/mds/Migrator.cc
index a9b6b80b7f0c1..c977d9b9f8425 100644
--- a/src/mds/Migrator.cc
+++ b/src/mds/Migrator.cc
@@ -2483,9 +2483,8 @@ void Migrator::handle_export_prep(const cref_t<MExportDirPrep> &m, bool did_assi
   map<inodeno_t, fragset_t> import_bound_fragset;
   for (const auto &bound : m->get_bounds()) {
     dout(10) << " bound " << bound << dendl;
-    import_bound_fragset[bound.ino].insert(bound.frag);
+    import_bound_fragset[bound.ino].insert_raw(bound.frag);
   }
-
   // assimilate contents?
   if (!did_assim) {
     dout(7) << "doing assim on " << *dir << dendl;
@@ -2515,6 +2514,7 @@ void Migrator::handle_export_prep(const cref_t<MExportDirPrep> &m, bool did_assi
     for (map<inodeno_t,fragset_t>::iterator p = import_bound_fragset.begin();
 	 p != import_bound_fragset.end();
 	 ++p) {
+      p->second.simplify();
       CInode *in = cache->get_inode(p->first);
       ceph_assert(in);
       in->get_stickydirs();
-- 
2.39.5