The task of concurrency control is to synchronize the user transactions on this data base and with this to avoid conflicts that lead to faulty or inconsistent data. Concurrency control has been subject to active research for quite some time and several concurrency control algorithms have been proposed and implemented. The relative performance of these methods varies depending on the system envi...

with the task placement problem in a straight way that allows us to go one step further, we have adopted an interconnection-network-based DRHW mode, which includes Operating System support to reallocate tasks at run-time. On top of this model we have applied an emerging task concurrency management (TCM) methodology initially developed for multiprocessor platforms with promising results. Moreove...

Database management systems (DBMSs) have been increasingly used for advanced application domains, such as software development environments, workjlow management systems, computer-aided design and manufacturing, and managed healthcare. In these domains, the standard correctness model of serializability is often too restrictive. We introduce the notion of a Concurrency Control Language (CCL) that...

Main-memory OLTP engines are being increasingly deployed on multicore servers that provide abundant thread-level parallelism. However, recent research has shown that even the state-of-the-art OLTP engines are unable to exploit available parallelism for high contention workloads. While previous studies have shown the lack of scalability of all popular concurrency control protocols, they consider...

We propose and evaluate an admission control paradigm for RTDBS, in which a transaction is submitted to the system as a pair of processes: a primary task and a compensating task. The execution requirements of the primary task are not known a priori, whereas those of the compensating task are known a priori. Upon the submission of a transaction , an Admission Control Mechanism is employed to dec...

Transactional memory (TM) offers optimistic concurrency support in modern multicore architectures, helping the programmers to extract parallelism in irregular applications when data dependence information is not available before runtime. In fact, recent research focus on exploiting thread-level parallelism using TM approaches. However, the proposed techniques are of general use, valid for any t...

We investigate the performance of concurrency mechanisms available on NVIDIA’s new Ampere GPU microarchitecture under deep learning training and inference workloads. In contrast to previous studies that treat as a black box, we examine scheduling at microarchitectural level. find lack fine-grained preemption mechanisms, robust task prioritization options, contention-aware thread block placement...