FPTree

An open-source FPTree implementation

I. Oukid, J. Lasperas, A. Nica, T. Willhalm, and W. Lehner. FPTree: A Hybrid SCM-DRAM Persistent and Concurrent B-Tree for Storage Class Memory. 
In Proceedings of the 2016 International Conference on Management of Data, SIGMOD’16, pages 371–386. ACM, 2016

Important information before installation

FPTree use Intel Threading Building Blocks (oneTBB) for concurrency control. The default retry threshold for oneTBB is only 10 for read write mutex.

To achieve better scalability, we are using customized TBB library for FPTree (which is also the approach taken by the original author).
Here are the steps to generate libtbb.so:
- Clone oneTBB from github (https://github.com/oneapi-src/oneTBB.git)
- Modify the read/write retry from 10 to 256 in oneTBB/src/tbb/rtm_mutex.cpp and oneTBB/src/tbb/rtm_rw_mutex.cpp
- $ cd oneTBB && mkdir build && cd build && cmake -DCMAKE_BUILD_TYPE=Release .. && make -jN
- Check that libtbb.so exists in oneTBB/build/gnu_11.1_cxx11_64_release
- Modify CMakeLists.txt located in FPTree folder to use custom TBB
  - delete -ltbb flag in CMAKE_CXX_FLAGS which link to your default TBB built
  - add and modify them in the proper place in CMakeLists.txt
```
  link_directories(oneTBB/build/gnu_11.1_cxx11_64_release) 
  include_directories(/yourpathtoTBB/oneTBB/include)
  target_link_libraries(fptree_pibench_wrapper libtbb.so)
```
Modify #define PMEMOBJ_POOL_SIZE in fptree.h if BACKEND = PMEM
Modify #define MAX_INNER_SIZE 128 and #define MAX_LEAF_SIZE 64 in fptree.h if you want. These are tunable variable.

Build

Build PMEM Version

mkdir build && cd build
cmake -DPMEM_BACKEND=PMEM ..

Build DRAM Version

mkdir build && cd build
cmake -DPMEM_BACKEND=DRAM ..

All executables are in build/src folder

Interative executable

Above command help you build fptree executable

It will pre-load 100 keys and then let you play with

Enter the key to insert, delete or update (-1):

Enter exit to leave the program and then it will perform the scan operation from the header leaf node

Inspector executable

mkdir build && cd build
cmake -DPMEM_BACKEND=${BACKEND} -DBUILD_INSPECTOR=1 ..

Run inspector to check the correctness of single/multi-threaded insert, delete operations for both leaf nodes and inner nodes

If you want to check performance of this implementation, please see PiBench instruction below

Other build options

-DBUILD_INSPECTOR=1 to build inspector executable which can check the correctness of single/multi-threaded operations (insert, delete..)

-DTEST_MODE=1 to set the size of leaf nodes & inner nodes. (TEST MODE: MAX_INNER_SIZE=3 MAX_LEAF_SIZE=4 for debug usage)

Benchmark on PiBench

We officially support FPTree wrapper for pibench:

Checkout PiBench here: https://github.com/sfu-dis/pibench

Build/Create FPTree shared lib

mkdir Release && cd Release
cmake -DPMEM_BACKEND=${BACKEND} -DTEST_MODE=0 -DBUILD_INSPECTOR=0 ..

xiaorz/fptree-1