The traditional lock manager (LM) seriously limits the transaction throughput of the main memory database systems (MMDB). In this paper, we introduce dependence-cognizant locking (DCLP), an efficient improvement to the traditional LM, which dramatically reduces the locking space while offering efficiency. With DCLP, one transaction and its direct successors are collocated in its context. Whenever a transaction is committed, it wakes up its direct successors immediately avoiding the expensive operations, such as lock detection and latch contention. We also propose virtual transaction which has better time and space complexity by compressing continuous read-only transactions/operations. We implement DCLP in Calvin and carry out experiments in both multicore and shared-nothing distributed databases. Experiments demonstrate that, in contrast with existing algorithms, DCLP can achieve better performance in many workloads, especially high-contention workloads.

中文翻译：

---

主内存数据库系统的依赖项识别锁定改进

传统锁管理器（LM）严重限制了主内存数据库系统（MMDB）的事务吞吐量。在本文中，我们介绍了依赖项识别锁定（DCLP），它是对传统LM的有效改进，它在提供效率的同时大大减少了锁定空间。在DCLP中，一项交易及其直接后继者在其上下文中并置在一起。无论何时提交事务，它都会立即唤醒其直接后继者，从而避免执行昂贵的操作，例如锁定检测和闩锁争用。我们还提出了通过压缩连续的只读事务/操作来具有更好的时间和空间复杂性的虚拟事务。我们在Calvin中实施DCLP，并在多核和无共享分布式数据库中进行实验。实验表明，