Software transactional memory (STM) is a promising technique for controlling concurrency in modern multi-processor architectures. STM aims to be more scalable than explicit coarse-grained locking and easier to use than fine-grained locking. However, STM implementations have yet to demonstrate that their runtime overheads are acceptable. To date, empiric evaluations of these implementations have suffered from the lack of realistic benchmarks. Measuring performance of an STM in an overly simplified setting can be at best uninformative and at worst misleading as it may steer researchers to try to optimize irrelevant aspects of their implementations. This paper presents STMBench7: a candidate benchmark for evaluating STM implementations. The underlying data structure consists of a set of graphs and indexes intended to be suggestive of many complex applications, e.g., CAD/CAM. A collection of operations is supported to model a wide range of workloads and concurrency patterns. Companion ...