This is a optimizer plugin base on PBA for GSLAM later then version 2.1.0, which implement parallel bundle adjust with GPU or multi-core CPU.
https://github.com/zdzhaoyong/GSLAM
mkdir build;cd build;cmake ..;sudo make install
bool bundleAdjust(GSLAM::BundleGraph& graph)
{
SPtr<GSLAM::Optimizer> optimizer=GSLAM::Optimizer::create("libgslam_optimizerPBA");
return optimizer->optimize(graph);
}