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@@ -1,11 +1,11 @@
 # The TinyKV Course
 
-This is a series of projects on a key-value storage system built with the Raft consensus algorithm. These projects are inspired by the famous [MIT 6.824](http://nil.csail.mit.edu/6.824/2018/index.html) course, but aim to be closer to industry implementations. The whole course is pruned from [TiKV](https://github.com/tikv/tikv) and re-written in Go. After completing this course, you will have the knowledge to implement a basic key-value storage fault-tolerance service with distributed transaction support and a better understanding of TiKV implementation.
+This is a series of projects on a key-value storage system built with the Raft consensus algorithm. These projects are inspired by the famous [MIT 6.824](http://nil.csail.mit.edu/6.824/2018/index.html) course, but aim to be closer to industry implementations. The whole course is pruned from [TiKV](https://github.com/tikv/tikv) and re-written in Go. After completing this course, you will have the knowledge to implement a horizontal scalable, high available, key-value storage service with distributed transaction support and a better understanding of TiKV implementation.
 
 The whole project is a skeleton code for a kv server and a scheduler server at initial, and you need to finish the core logic step by step:
 
 - Project1: build a standalone key-value server
-- Project2: build a fault tolerant key-value server with Raft
+- Project2: build a high available key-value server with Raft
 - Project3: support multi Raft group and balance scheduling on top of Project2
 - Project4: support distributed transaction on top of Project3
 
@@ -13,7 +13,9 @@ The whole project is a skeleton code for a kv server and a scheduler server at i
 
 ## Course
 
-Before starting, you’d better read the overview design of TiKV and PD to get a general impression on what you will build:
+Here is a [reading list](doc/reading_list.md) for the knowledge of distributed storage system. Though not all of them are highly related with this course, it can help you construct the knowledge system in this field.
+
+Also, you’d better read the overview design of TiKV and PD to get a general impression on what you will build:
 
 - TiKV
   - <https://pingcap.com/blog-cn/tidb-internal-1/> (Chinese Version)
@@ -50,10 +52,10 @@ The whole project is organized into the following directories:
 
 Please follow the course material to learn the background knowledge and finish code step by step.
 
-- [Project1 - StandaloneKV](courses/project1-StandaloneKV.md)
-- [Project2 - RaftKV](courses/project2-RaftKV.md)
-- [Project3 - MultiRaftKV](courses/project3-MultiRaftKV.md)
-- [Project4 - Transaction](courses/project4-Transaction.md)
+- [Project1 - StandaloneKV](doc/project1-StandaloneKV.md)
+- [Project2 - RaftKV](doc/project2-RaftKV.md)
+- [Project3 - MultiRaftKV](doc/project3-MultiRaftKV.md)
+- [Project4 - Transaction](doc/project4-Transaction.md)
 
 ## Deploy a cluster
 
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+- Storage Engine
+  - Disk I/O
+    - Flavors of I/O
+      - <https://medium.com/databasss/on-disk-io-part-1-flavours-of-io-8e1ace1de017>
+      - <https://medium.com/databasss/on-disk-io-part-2-more-flavours-of-io-c945db3edb13?>
+    - Amplification and RUM
+      - <http://smalldatum.blogspot.com/2015/11/read-write-space-amplification-pick-2_23.html>
+      - <http://daslab.seas.harvard.edu/rum-conjecture/>
+      - <http://smalldatum.blogspot.com/2019/05/crum-conject>
+        ure-read-write-space-and.html
+  - B-Tree (Optional)
+    - Reading Materials
+      - Database Internals: 2. B-Tree Basics
+      - Database Internals: 3. File Formats
+      - Database Internals: 4. Implementing B-Trees
+    - Reference
+      - <https://www.cs.usfca.edu/~galles/visualization/Algorith>
+      ms.html
+      - <https://github.com/etcd-io/bbolt>
+  - LSM-Tree
+    - Reading Materials
+      - Database Internals: 7. Log-Structured Storage
+    - Reference
+      - <https://github.com/google/leveldb>
+      - <https://github.com/facebook/rocksdb>
+      - <https://github.com/syndtr/goleveldb>
+    - B-Tree vs LSM-tree
+      - <https://tikv.org/docs/deep-dive/key-value-engine/b-tree-vs-lsm/>
+  - LSM-Tree Evolution
+    - Wisckey
+      - <https://www.usenix.org/system/files/conference/fast16/fast16-papers-lu.pdf>
+    - HashKV (Optional)
+      - <https://www.usenix.org/system/files/conference/atc18/atc18-chan.pdf>
+    - Monkey (Optional)
+      - <https://stratos.seas.harvard.edu/files/stratos/files/monkeykeyvaluestore.pdf>
+    - Reference
+      - <https://github.com/dgraph-io/badger>
+      - <https://github.com/tikv/titan>
+- Serializing & RPC
+  - Protocol Buffer
+    - Reading Materials
+      - <https://developers.google.com/protocol-buffers/docs/overview>
+    - Reference
+      - <https://github.com/dgraph-io/badger>
+      - <https://github.com/protocolbuffers/protobuf>
+  - gRPC
+    - Reading Materials
+      - <https://www.grpc.io/docs/quickstart/go/>
+    - Reference
+      - <https://github.com/grpc/grpc-go>
+- Data Partitioning
+  - Range vs Hash
+    - <https://tikv.org/docs/deep-dive/scalability/data-sharding/>
+  - Partitioning of DynamoDB (Optional)
+    - <https://www.allthingsdistributed.com/files/amazon-dynamo-sosp2007.pdf>
+    - <https://dzone.com/articles/partitioning-behavior-of-dynamodb>
+  - Partitioning of TiKV
+    - <https://pingcap.com/blog/2017-07-11-tidbinternal1/>
+- Replication & Consistency
+  - Reading Materials
+    - Database Internals: 11. Replication and Consistency
+  - CAP vs PACELE
+    - <http://www.cs.umd.edu/~abadi/papers/abadi-pacelc.pdf>
+  - Clock and Time
+    - <https://dzone.com/articles/tick-or-tock-keeping-time-and-order-in-distributed-1>
+  - Consistency
+    - <https://arxiv.org/pdf/1902.03305.pdf>
+- Consensus
+  - Quorum
+    - <https://en.wikipedia.org/wiki/Quorum_(distributed_computing)>
+  - Paxos (Optional)
+    - Reading Materials
+      - Database Internals: 14. Consensus @ Paxos
+    - Reference
+      - <https://lamport.azurewebsites.net/pubs/paxos-simple.pdf>
+  - Raft
+    - Reading Materials
+      - Database Internals: 14. Consensus @ Raft
+    - Reference
+      - <https://raft.github.io/>
+      - <https://pdos.csail.mit.edu/6.824/labs/lab-raft.html>
+- Scale & Balance
+  - Multi-Raft
+    - <https://tikv.org/docs/deep-dive/scalability/multi-raft/>
+  - Split & Merge
+    - <https://pingcap.com/blog/2017-07-20-tidbinternal3/>
+  - Balance
+    - <https://pingcap.com/blog/2017-07-20-tidbinternal3/>
+- Distributed Transactions
+  - Reading Materials
+    - Database Internals: 5. Transaction Processing and Recovery
+    - Database Internals: 13. Distributed Transactions
+  - ACID
+    - <https://en.wikipedia.org/wiki/ACID>
+  - Isolation (Optional)
+    - <https://www.microsoft.com/en-us/research/wp-content/uploads/2016/02/tr-95-51.pdf>
+    - <https://www.jianshu.com/p/3673e612cce2> (Chinese)
+  - Spanner (Optional)
+    - <https://storage.googleapis.com/pub-tools-public-publication-data/pdf/45855.pdf>
+    - <https://www.jianshu.com/p/f307bd2023f5> (Chinese)
+  - Percolator
+    - <https://tikv.org/docs/deep-dive/distributed-transaction/percolator/>
+    - <https://tikv.org/docs/deep-dive/distributed-transaction/optimized-percolator/>
+- Coprocessor (Optional)
+  - <https://blogs.apache.org/hbase/entry/coprocessor_introduction>
+  - <https://zhuanlan.zhihu.com/p/89518391> (Chinese)
+- Benchmark & Testing
+  - sysbench (Optional)
+    - <https://github.com/akopytov/sysbench>
+    - <https://www.percona.com/blog/2019/04/25/creating-custom-sysbench-scripts/>
+    - <https://www.jianshu.com/p/30933e0bebe7> (Chinese)
+  - go-tpc (Optional)
+    - <https://github.com/pingcap/go-tpc>
+  - go-ycsb
+    - <https://github.com/pingcap/go-ycsb>
+    - <https://medium.com/@siddontang/use-go-ycsb-to-benchmarkdifferent-databases-8850f6edb3a7>
+    - <https://www.jianshu.com/p/73d22befe47d> (Chinese)
+  - Chaos
+    - <https://principlesofchaos.org/>
+    - <https://pingcap.com/blog/chaos-practice-in-tidb/>
+    - <https://medium.com/@siddontang/use-chaos-to-test-the-distributed-system-linearizability-4e0e778dfc7d>