Simultaneous localization and mapping (SLAM) is an important tool that enables autonomous navigation of mobile robots through unknown environments. As the name SLAM suggests, it is important to obtain a correct representation of the environment and estimate a correct trajectory of the robot poses in the map. Dominant state-of-the-art approaches solve the pose estimation problem using graph optimization techniques based on the least squares minimization method. Among the most popular approaches are libraries such as g²o, Ceres, GTSAM and SE-Sync. The aim of this paper is to describe these approaches in a unified manner and to evaluate them on an array of publicly available synthetic and real-world pose graph datasets. In the evaluation experiments, the computation time and the value of the objective function of the four optimization libraries are analyzed.