1.2 What is a Data Race?

The Thread Analyzer detects data races that occur during the execution of a multithreaded process. A data race occurs when all of the following are true:

• Two or more threads in a single process access the same memory location concurrently

• At least one of the accesses is for writing

• The threads are not using any exclusive locks to control their accesses to that memory

When these three conditions hold, the order of accesses is non-deterministic, and the computation may give different results from run to run depending on that order. Some data races may be benign (for example, when the memory access is used for a busy-wait), but many data races are bugs in the program.

The Thread Analyzer works on a multithreaded program written using the POSIX thread API, Solaris thread API, OpenMP, or a mix of these.