diff --git a/src/observer/storage/buffer/buffer_LRU.cpp b/src/observer/storage/buffer/buffer_LRU.cpp
new file mode 100644
index 000000000..8a74708d7
--- /dev/null
+++ b/src/observer/storage/buffer/buffer_LRU.cpp
@@ -0,0 +1,163 @@
+#include "pch.h"
+#include "buffer_LRU.h"
+#include "time.h"
+#define CLOCKS_PER_SEC  ((clock_t)1000)
+clock_t start, t_end; double duration;
+
+void str2int(int& int_temp, const string& string_temp)
+{
+	stringstream stream(string_temp);
+	stream >> int_temp;
+}
+
+vector<string> split(const string& str, const string& delim) {
+	vector<string> res;
+	if ("" == str) return res;
+	char* strs = new char[str.length() + 1];
+	strcpy(strs, str.c_str());
+
+	char* d = new char[delim.length() + 1];
+	strcpy(d, delim.c_str());
+
+	char* p = strtok(strs, d);
+	while (p) {
+		string s = p;
+		res.push_back(s);
+		p = strtok(NULL, d);
+	}
+	delete strs, d;
+	return res;
+}
+
+void CreateBlockWRTest(int blocks)
+{
+	FILE* fstream_w;
+	char dbfile[] = "database.dbf";
+	fstream_w = fopen(dbfile, "wb");
+	if (fstream_w == NULL)
+	{
+		printf("open or create file failed!\n");
+		exit(1);
+	}
+	else {
+		//cout << "Open " << dbfile << " successfully!" << endl;
+	}
+	// 数据块号
+	unsigned int block_num = 0;
+	// 时间戳
+	unsigned int btimestamp = 0;
+	// 偏移量表
+	unsigned short int offset[FRAMESIZE / RECORDSIZE];
+	int BLOCK_HEAD = sizeof(btimestamp) + sizeof(offset);
+	for (int i = 0; i < FRAMESIZE / RECORDSIZE; i++) { offset[i] = BLOCK_HEAD + i * RECORDSIZE; };
+
+	for (int j = 0; j < blocks; j++)
+	{
+		// 写入块首部
+		block_num = j;
+		int writeCnt = fwrite(&block_num, sizeof(block_num), 1, fstream_w); // // 数据块号
+		writeCnt = fwrite(&btimestamp, sizeof(btimestamp), 1, fstream_w);  // 时间戳
+		writeCnt = fwrite(&offset, sizeof(offset), 1, fstream_w); // 块内偏移表
+		// 写入记录
+		char* p_schema = NULL;
+		unsigned int timestamp = j;
+		unsigned int length = 316;
+		char namePtr[32];
+		char adrressPtr[256];
+		char genderPtr[4];
+		char birthdayPtr[12];
+		for (int i = 0; i < FRAMESIZE / RECORDSIZE; i++)
+		{
+			writeCnt = fwrite(&fstream_w, sizeof(fstream_w), 1, fstream_w);
+			writeCnt = fwrite(&length, sizeof(length), 1, fstream_w);
+			writeCnt = fwrite(&timestamp, sizeof(timestamp), 1, fstream_w);
+			writeCnt = fwrite(&namePtr, sizeof(namePtr), 1, fstream_w);
+			writeCnt = fwrite(&adrressPtr, sizeof(adrressPtr), 1, fstream_w);
+			writeCnt = fwrite(&genderPtr, sizeof(genderPtr), 1, fstream_w);
+			writeCnt = fwrite(&birthdayPtr, sizeof(birthdayPtr), 1, fstream_w);
+		}
+		char null[272]; //  填充字节使得4KB对齐
+		writeCnt = fwrite(&null, sizeof(null), 1, fstream_w);
+	}
+
+
+	fclose(fstream_w);
+}
+
+
+void NoIndexQuery(int find_block_num)
+{
+	FILE* fstream_r;
+	fstream_r = fopen("database.dbf", "rb");
+	unsigned int blocknum = 0;
+	cout << "query target: " << find_block_num << endl;
+	int offset = find_block_num * FRAMESIZE;
+	fseek(fstream_r, offset, SEEK_SET);
+	int readCnt = fread(&blocknum, sizeof(blocknum), 1, fstream_r);
+	cout << " query result: " << blocknum << endl;
+
+	fclose(fstream_r);
+}
+
+void processTrace(int page_id, int operation, LRU* LRUCache) {
+	if (operation == 0)
+	{
+#if VERBOSE
+		cout << "---[trace 读操作] 读取page_id:" << page_id << " 的数据---" << endl;
+#endif
+		LRUCache->readData(page_id);
+	}
+	else if (operation == 1)
+	{
+#if VERBOSE
+		cout << "---[trace 写操作] 修改page_id:" << page_id << " 的数据---" << endl;
+#endif
+		LRUCache->writeData(page_id, NULL);
+	}
+}
+
+
+int main()
+{
+	cout << "*****************************************" << endl;
+	cout << "*****************************************" << endl;
+	cout << "\n";
+	CreateBlockWRTest(50000);
+	string tracefilename = "data-5w-50w-zipf.txt";
+	ifstream traceFile(tracefilename.c_str());
+	if (!traceFile)
+	{
+		cout << "Error opening " << tracefilename << " for input" << endl;
+		exit(-1);
+	}
+	else {
+		cout << "Open " << tracefilename << " successfully!" << endl;
+	}
+	char dbpath[] = "database.dbf";
+	LRU LRU(BUFFSIZE, dbpath);
+	int wr = 0;
+	int page_id = 0;
+	string trace;
+	int request_num = 0;
+	cout << "缓冲区大小:" << BUFFSIZE << endl;
+	start = clock();
+	while (!traceFile.eof())
+	{
+		getline(traceFile, trace);
+		std::vector<string> res = split(trace, ",");
+		str2int(wr, res[0]);
+		str2int(page_id, res[1]);
+		processTrace(page_id, wr, &LRU);
+		request_num++;
+	}
+	t_end = clock();
+	LRU.saveDirty2Disk();
+	cout << "读写总数:" << request_num << endl;
+	cout << "IO总数:" << LRU.getIOnum() << endl;
+	cout << "命中总数:" << LRU.getHitNum() << endl;
+	printf("命中率:%f%%\n", 100 * LRU.getHitNum() / float(request_num));
+	duration = ((double)t_end - start) / CLOCKS_PER_SEC;
+	printf("平均读写时间: %f ms\n", duration);
+	system("pause");
+	traceFile.close();
+}
diff --git a/src/observer/storage/buffer/buffer_LRU.h b/src/observer/storage/buffer/buffer_LRU.h
new file mode 100644
index 000000000..3efc1b451
--- /dev/null
+++ b/src/observer/storage/buffer/buffer_LRU.h
@@ -0,0 +1,329 @@
+#include "stdio.h"
+#include <iostream>
+#include <fstream>
+#include <sstream>
+#include <string>
+#include <vector>
+#include <unordered_map>
+#include <stack>
+
+#define VERBOSE 0
+#define RECORDSIZE 316
+#define FRAMESIZE 4096 
+#define BUFFSIZE 1024 // 可修改缓冲区大小
+#define MAXSIZE  FRAMESIZE*BUFFSIZE
+
+using namespace std;
+
+struct bFrame
+{
+	char field[FRAMESIZE];
+};
+
+struct bBuff
+{
+	bFrame frames[BUFFSIZE];
+};
+
+
+
+struct Record
+{
+	int page_id;
+	int slot_num;
+};
+
+struct Frame
+{
+	int frame_id;
+	int offset;
+};
+
+
+class DiskSpaceManager {
+private:
+	FILE* fstream;
+public:
+	DiskSpaceManager() :fstream(NULL) {}
+
+	void openFile(char filepath[]) {
+		fstream = fopen(filepath, "rb+");
+	}
+
+	void readDisk(int page_id, int frame_id, bBuff* buff) {
+		bFrame bframe;
+		unsigned int block_num = 0;
+		fseek(fstream, page_id * FRAMESIZE, SEEK_SET);
+		if (fread(&bframe.field, sizeof(bframe.field), 1, fstream) == 1) {
+#if VERBOSE
+			cout << "读取 page_id:" << page_id << " 到 frame_id:" << frame_id << " ... 缓存成功。" << endl;
+#endif
+		}
+		else {
+#if VERBOSE
+			cout << "读取 page_id:" << page_id << " 到 frame_id:" << frame_id << " ... 缓存失败！" << endl;
+#endif
+		}
+		buff->frames[frame_id] = bframe;
+	}
+
+	void writeDisk(int page_id, int frame_id, bBuff* buff) {
+		bFrame bframe = buff->frames[frame_id];
+		fseek(fstream, page_id * FRAMESIZE, SEEK_SET);
+		if (fwrite(&bframe.field, sizeof(bframe.field), 1, fstream) == 1) {
+#if VERBOSE
+			cout << "写入 frame_id:" << frame_id << " 到 page_id:" << page_id << " 磁盘成功。" << endl;
+#endif
+		}
+		else {
+#if VERBOSE
+			cout << "写入 frame_id:" << frame_id << " 到 page_id:" << page_id << " 磁盘失败！" << endl;
+#endif
+		}
+	}
+};
+
+//双向链表+哈希表实现LRU
+struct BufferControlBlocks
+{
+	int page_id, frame_id, ref, count, time, dirty;
+	BufferControlBlocks* _prev;
+	BufferControlBlocks* _next;
+	BufferControlBlocks() : _next(NULL), _prev(NULL) {}
+	BufferControlBlocks(int page_id, int frame_id) : page_id(page_id), frame_id(frame_id), count(0), time(0), dirty(0) { BufferControlBlocks(); }
+	void disconnect() {
+		if (_prev) _prev->_next = _next;
+		if (_next) _next->_prev = _prev;
+	}
+	void Insert(BufferControlBlocks* node) {
+		if (_next) {
+			node->_prev = this; // this
+			_next->_prev = node;
+			node->_next = _next;
+			_next = node;
+		}
+	}
+};
+// 储存frames和pages的元数据Buffer Control Blocks
+class LRU {
+private:
+	int size, capacity; //当前大小，容量上限
+	unordered_map<int, BufferControlBlocks*> hashmap;
+	stack<int> frame_ids;
+	BufferControlBlocks* head, * tail;
+	int hitNum; // 命中数
+	int IONum; // 磁盘IO
+	bBuff* buff;
+	int f2p[BUFFSIZE]; // frame_id到page_id的映射
+	DiskSpaceManager diskSpaceManager;
+public:
+	LRU(int capacity, char dbpath[]) : size(0), capacity(capacity) {
+		head = new BufferControlBlocks;
+		tail = new BufferControlBlocks;
+		head->_next = tail;
+		tail->_prev = head;
+		hitNum = IONum = 0;
+		buff = new bBuff;
+		diskSpaceManager.openFile(dbpath);
+		for (int i = 0; i < BUFFSIZE; i++)f2p[i] = 0;
+		for (int i = 0; i < capacity; i++)frame_ids.push(i);
+	}
+	int read(int page_id) {
+		if (hashmap.find(page_id) == hashmap.end()) {
+#if VERBOSE
+			cout << "该page_id: " << page_id << " 未存在于缓存中！" << endl;
+#endif
+			return -1;
+		}
+		BufferControlBlocks* node = hashmap[page_id];
+		node->disconnect();
+		head->Insert(node);
+		int fid = node->frame_id;
+		return fid;
+	}
+
+	int read_id(int page_id) {
+		if (hashmap.find(page_id) == hashmap.end()) {
+#if VERBOSE
+			cout << "该page_id: " << page_id << " 未存在于缓存中！";
+#endif
+			return -1;
+		}
+		BufferControlBlocks* node = hashmap[page_id];
+		return node->frame_id;
+	}
+
+	int put(int page_id, int frame_id = 0) {
+		BufferControlBlocks* node;
+		if (page_id == -1) { cout << "申请磁盘新page" << endl; };
+		if (hashmap.find(page_id) == hashmap.end()) {
+			if (size < capacity) {
+				frame_id = frame_ids.top();
+				frame_ids.pop();
+				node = new BufferControlBlocks(page_id, frame_id);
+				size++;
+			}
+			else
+			{
+				// 置换
+				node = tail->_prev;
+				int i = 0;
+				for (; node->ref > 1 || node->count > 1; node = node->_next)
+				{
+					node->ref = 0; i++; if (i == capacity - 1) { cout << "警告：缓存溢出！进行强行置换"; };
+					break;
+				};
+				// 脏数据写入磁盘
+				if (node->dirty)
+				{
+					node->dirty = 0;
+					diskSpaceManager.writeDisk(node->page_id, node->frame_id, buff);
+#if VERBOSE
+					cout << "缓存区满，发生置换，已将page_id:" << node->page_id << " 数据块写入磁盘！" << endl;
+#endif
+				}
+				frame_id = node->frame_id;
+				node->disconnect();
+				hashmap.erase(node->page_id);
+				node->page_id = page_id;
+				node->frame_id = frame_id;
+			}
+			hashmap[page_id] = node;
+			head->Insert(node);
+		}
+		else {
+			node = hashmap[page_id];
+			node->disconnect();
+			head->Insert(node);
+			frame_id = node->frame_id;
+		}
+		return frame_id;
+	}
+
+	int selectVictim() {
+		BufferControlBlocks* node;
+		node = tail->_prev;
+		int i = 0;
+		for (; node->ref > 1 || node->count > 1; node = node->_next)
+		{
+			node->ref = 0; i++; if (i == capacity) { cout << "缓存溢出！即将进行强行置换"; };
+		};
+		return node->frame_id;
+	}
+
+	void remove(int page_id) {
+		if (hashmap.find(page_id) == hashmap.end()) {
+			cout << "错误！page_id: " << page_id << " 不存在缓存中！" << endl;
+		}
+
+		BufferControlBlocks* node = hashmap[page_id];
+		frame_ids.push(node->frame_id);
+		node->disconnect();
+		hashmap.erase(node->page_id);
+		size--;
+	}
+
+	int setDirty(int page_id) {
+		if (hashmap.find(page_id) == hashmap.end()) {
+			return -1;
+		}
+		BufferControlBlocks* node = hashmap[page_id];
+		node->dirty = 1;
+		node->time += 1;
+		node->disconnect(); // �����ײ�
+		head->Insert(node);
+		return node->frame_id;
+	}
+
+	int setCount(int page_id) {
+		if (hashmap.find(page_id) == hashmap.end()) {
+			return -1;
+		}
+		BufferControlBlocks* node = hashmap[page_id];
+		node->count += 1;
+		node->time += 1;
+		node->disconnect();
+		head->Insert(node);
+		return node->frame_id;
+	}
+
+	unsigned int readData(int page_id) {
+		int frame_id = read(page_id);
+		if (frame_id == -1)
+		{
+
+			IONum++;
+			frame_id = put(page_id);
+			diskSpaceManager.readDisk(page_id, frame_id, buff);
+		}
+		else {
+
+			hitNum++;
+		}
+#if VERBOSE
+		unsigned int* bln_ptr;
+		char bln[4];
+		for (int i = 0; i < 4; i++)
+		{
+			bln[i] = buff->frames[frame_id].field[i];
+		}
+		bln_ptr = (unsigned int*)&bln;
+		cout << "读到的数据（块号）:" << *bln_ptr << " （指针指向块头，读取长度为4bit，记录着该块在整个.dbf文件的块号）" << endl;
+		if (*bln_ptr == page_id) cout << "读取数据验证通过!" << endl;
+#endif
+		return 1;
+	}
+
+	int writeData(int page_id, char* data) {
+		int frame_id = read(page_id);
+		if (frame_id == -1)
+		{
+
+			IONum++;
+			frame_id = put(page_id);
+			diskSpaceManager.readDisk(page_id, frame_id, buff);
+		}
+		else {
+
+			hitNum++;
+		}
+		buff->frames[frame_id].field[1]++;
+		BufferControlBlocks* node = hashmap[page_id];
+		node->dirty = 1;
+#if VERBOSE
+		unsigned int* timestamp;
+		char ts[4];
+		for (int i = 0; i < 4; i++)
+		{
+			ts[i] = buff->frames[frame_id].field[4 + i];
+		}
+		timestamp = (unsigned int*)&ts;
+		cout << "即将写入的数据（时间戳）:" << *timestamp << " （指针指向距离块头4bit位置，写入长度为4bit，记录着该块的时间戳）" << endl;;
+#endif
+		return 1;
+	}
+
+	int getIOnum() {
+		return IONum;
+	}
+
+	int getHitNum() {
+		return hitNum;
+	}
+
+	void saveDirty2Disk() {
+		for (BufferControlBlocks* node = head->_next; node != tail; node = node->_next)
+		{
+			if (node->dirty == 1)
+			{
+				diskSpaceManager.writeDisk(node->page_id, node->frame_id, buff);
+				IONum++;
+				node->dirty = 0;
+			}
+		}
+		delete tail, head, buff;
+#if VERBOSE
+		cout << "即将关闭LRUCache: 已将全部脏数据写进磁盘!" << endl;
+#endif
+	}
+};