The Essential OpenMP

Abstract OpenMP is among the most widely used parallel programming application programming interfaces (APIs) and is largely directive based, making it one of the most accessible parallel programming APIs available. OpenMP targets shared-memory architectures and is limited in scalability to hardware system architectures providing near uniform memory access to shared memory. OpenMP supports the fork–join model of parallel computing where at particular points in the execution the master thread spawns a number of threads that are executed concurrently to gain a performance benefit. Furthermore, OpenMP is a shared-memory model allowing direct access to global variables by all threads of a user process. This chapter explores some of the essential features of OpenMP and introduces basic OpenMP semantics.