MOD

Debugging and tuning database systems is very challenging. Using common profiling tools is often not sufficient because they identify the machine instruction rather than the instance of a data structure that causes a performance problem. This leaves a ...

Multi-core scalability is one of the most important features for database systems running on today's hardware. Not surprisingly, the implementation of locks is paramount to achieving efficient and scalable synchronization. In this work, we identify the ...

In this paper, we set out the goal to revisit the results of "Starring into the Abyss [...] of Concurrency Control with [1000] Cores" [27] and analyse in-memory DBMSs on today's large hardware. Despite the original assumption of the authors, today we do ...

New data storage technologies such as the recently introduced Intel^® Optane^™ DC Persistent Memory Module (PMM) offer exciting opportunities for optimizing the query processing performance of database workloads. In particular, the unique combination of ...

Database systems rely upon statistical synopses for cardinality estimation. A very versatile and powerful method for estimation purposes is to maintain a random sample of the data. However, drawing a random sample of an existing data set is quite ...

Query compilation can make query execution extremely efficient, but it introduces additional compilation time. The compilation time causes a relatively high overhead especially for short-running and high-complexity queries.

We propose Flounder IR as a ...

Getting the best performance from the ever-increasing number of hardware platforms has been a recurring challenge for data processing systems. In recent years, the advent of data science with its increasingly numerous and complex types of analytics has ...

Re-Pair is a compression algorithm well-suited for applications that require random accesses to compressed data, but has not found widespread use in the data management community due to its prohibitively high compression times. As Re-Pair is a ...

An efficient compression of integer vectors is critical in dictionary-encoded column stores like SAP HANA to keep more data in the limited and precious main memory. Past research focused on lightweight compression techniques that trade low latency of ...

Massive data transfers in modern key/value stores resulting from low data-locality and data-to-code system design hurt their performance and scalability. Near-data processing (NDP) designs represent a feasible solution, which although not new, have yet ...

As a result of recent improvements in FPGA technology, their benefits for highly efficient data processing pipelines are becoming more and more apparent. However, traditional RTL methods for programming FPGAs require knowledge of digital design and ...

Query execution techniques constantly adapt to novel hardware features to achieve high query performance, in particular for analytical queries. In recent years, vectorization based on the Single Instruction Multiple Data (SIMD) parallel paradigm has ...

In recent years we have seen a proliferation of FPGA-based key value stores (KVSs) [1--3, 5--7, 10] driven by the need for more efficient large-scale data management and storage solutions. In this context, FPGAs are useful because they offer network-...

Non-volatile memory (NVM) is an emerging technology, which has the persistence characteristics of large capacity storage devices, while providing the low access latency and byte-addressablity of traditional DRAM memory. In this paper, we provide ...

Persistent Memory (PM) represents a very promising, next-generation memory solution with a significant impact on database architectures. Several data structures for this new technology have already been proposed. However, primarily only complete ...

In this paper we conduct an empirical study across modern GPU-accelerated DBMSes with TPC-H workloads. Our rigorous experiments demonstrate that the studied DBMSes appear to utilize GPU resource effectively but do not scale well with growing databases ...

Hardware acceleration of database query processing can be done with the help of FPGAs. In particular, they are partially reconfigurable at runtime, which allows for the adaptation to a variety of queries. Reconfiguration itself, however, takes some ...

The Word-Aligned Hybrid (WAH) compression is a prominent example of a lightweight compression scheme for bitmap indices that considers the word size of the underlying architecture. This is a compromise toward commodity CPUs, where operations below the ...