From 9a270859a7a77d9d0673c5464e80775422598271 Mon Sep 17 00:00:00 2001
From: dgy <dinggyecnu@outlook.com>
Date: Sat, 28 Dec 2024 16:24:41 +0000
Subject: [PATCH] update unorderediter

---
 db/db_impl.cc        |  3 ++-
 db/dbformat.h        |  4 ++--
 db/unordered_iter.cc | 36 ++++++++++++++++++++++++++----------
 3 files changed, 30 insertions(+), 13 deletions(-)

diff --git a/db/db_impl.cc b/db/db_impl.cc
index 1bda06b..c26edbe 100644
--- a/db/db_impl.cc
+++ b/db/db_impl.cc
@@ -1766,7 +1766,7 @@ Status DBImpl::ReadValueLog(uint64_t file_id, uint64_t offset,
   std::string file_name_ = ValueLogFileName(dbname_, file_id);
 
   mutex_.Lock();
-  if(file_id==valuelogfile_number_){
+  if(file_id==valuelogfile_number_||config::mem_value_log_number==0){
     mutex_.Unlock();
     
     std::ifstream inFile(file_name_, std::ios::in | std::ios::binary);
@@ -1776,6 +1776,7 @@ Status DBImpl::ReadValueLog(uint64_t file_id, uint64_t offset,
 
     char buf[value_len];
     inFile.read(buf,value_len);
+    inFile.close();
     *value=std::string(buf,value_len);
     return Status::OK();
   }
diff --git a/db/dbformat.h b/db/dbformat.h
index 61ad581..e0dce4a 100644
--- a/db/dbformat.h
+++ b/db/dbformat.h
@@ -47,9 +47,9 @@ static const int kReadBytesPeriod = 1048576;
 // maximum size of value_log file
 static const int value_log_size=1<<26;
 //1<<33/1<<26=1<<7
-static const int mem_value_log_number=1<<8;//8GB
+static const int mem_value_log_number=0;//8GB
 
-static const int max_unorder_iter_memory_usage=32<<20; //32MB
+static const int max_unorder_iter_memory_usage=64<<20; //32MB
 
 }  // namespace config
 
diff --git a/db/unordered_iter.cc b/db/unordered_iter.cc
index 247b6cd..55ca072 100644
--- a/db/unordered_iter.cc
+++ b/db/unordered_iter.cc
@@ -52,6 +52,8 @@ class UnorderedIter : public Iterator {
       current_file->close();
       delete current_file;
     }
+    if(buf_for_now_key)delete buf_for_now_key;
+    if(buf_for_now_value)delete buf_for_now_value;
     delete iter_; 
   }
   bool Valid() const override { return mode!=2; }
@@ -91,18 +93,25 @@ class UnorderedIter : public Iterator {
     current_file->seekg(offset);
     current_file->read((char*)(&value_len),sizeof(uint64_t));
 
-    char buf[value_len];
-    current_file->read(buf,value_len);
-    buf_for_now_value=std::string(buf,value_len);
+    if(value_len>buf_for_now_value_size){
+      buf_for_now_value_size=value_len;
+      if(buf_for_now_value)delete buf_for_now_value;
+      buf_for_now_value=new char[value_len];
+    }
+    current_file->read(buf_for_now_value,value_len);
 
     current_file->read((char*)(&key_len),sizeof(uint64_t));
 
-    char key_buf[key_len];
-    current_file->read(key_buf,key_len);
-    buf_for_now_key=std::string(key_buf,key_len);
+    if(key_len>buf_for_now_key_size){
+      buf_for_now_key_size=key_len;
+      if(buf_for_now_key)delete buf_for_now_key;
+      buf_for_now_key=new char[key_len];
+    }
+
+    current_file->read(buf_for_now_key,key_len);
 
-    now_key=Slice(buf_for_now_key);
-    now_value=Slice(buf_for_now_value);
+    now_value=Slice(buf_for_now_value,value_len);
+    now_key=Slice(buf_for_now_key,key_len);
   }
 
   
@@ -110,8 +119,10 @@ class UnorderedIter : public Iterator {
   Iterator* const iter_;
   Slice now_value;
   Slice now_key;
-  std::string buf_for_now_key;
-  std::string buf_for_now_value;
+  int buf_for_now_key_size=0;
+  char* buf_for_now_key=nullptr;
+  int buf_for_now_value_size=0;
+  char* buf_for_now_value=nullptr;
   bool iter_valid=false;
   std::map<uint64_t,std::vector<uint64_t>> valuelog_map;
   int memory_usage=0;
@@ -156,6 +167,11 @@ void UnorderedIter::Next() {
     
     valuelog_map_iter=valuelog_map.begin();
     if(valuelog_map_iter!=valuelog_map.end()){
+      
+      for(auto it=valuelog_map.begin();it!=valuelog_map.end();it++){
+        std::sort(it->second.begin(),it->second.end());
+      }
+
       std::string file_name_ = ValueLogFileName(db_name_, valuelog_map_iter->first);
       assert(!current_file);
       current_file=new std::ifstream(file_name_, std::ios::in | std::ios::binary);