FlexPushdownDB

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A research cloud OLAP engine using hybrid caching and computation pushdown.

[1] Yifei Yang, Matt Youill, Matthew Woicik, Yizhou Liu, Xiangyao Yu, Marco Serafini, Ashraf Aboulnaga, Michael Stonebraker, FlexPushdownDB: Hybrid Pushdown and Caching in a Cloud DBMS, VLDB 2021.

Dependencies

To install required dependencies:

git clone https://github.com/cloud-olap/FlexPushdownDB
cd FlexPushdownDB

sudo ./setup.sh

Or specifically for Ubuntu systems, run

sudo ./tools/project/bin/ubuntu-prerequisites.sh

Build

Compiler needed: LLVM-10 or later versions.

To load CMake project:

mkdir build
cd build
cmake -DCMAKE_BUILD_TYPE=RelWithDebInfo -DCMAKE_C_COMPILER=/usr/bin/clang-10 -DCMAKE_CXX_COMPILER=/usr/bin/clang++-10 -G "CodeBlocks - Unix Makefiles" ..

To build the core of engine:

cmake --build . --target normal-pushdown

To build the executable of query execution using SSB benchmark:

cmake --build . --target normal-ssb-experiment

To build the executable for query generator of SSB queries:

cmake --build . --target normal-ssb-query-generate-file

Run

To run a batch of queries:

Put a batch of queries into <build_directory>/normal-ssb/sql/generated/, or run the query generator shown below, then:

./normal-ssb-experiment <cache_size> <mode> <caching_policy>

Configurations:

cache_size: allocated space of the segment cache.

Float number with GB unit

mode: whether to enable caching and pushdown capabilities.

1 - Pullup
2 - Pushdown-only
3 - Caching-only
4 - Hybrid

caching_policy: cache replacement policy used in the segment cache.

1 - LRU
2 - LFU
3 - Weighted-LFU
4 - Belady

To generate a batch of queries:

./normal-ssb-query-generate-file <type> <size> <skewness>

Configurations:

type: the workload type.

1 - SSB workload
2 - The workload involving different pushdown cost, used for benchmarking Weighted-LFU caching policy

size: number of queries in the batch generated.

skewness: parameter of Zipfian distribution, which we adopt in the workload.