The CMS Reconstruction Software

We report on the status and plans for the event reconstruction software of the CMS experiment. The CMS reconstruction algorithms are the basis for a wide range of data analysis approaches currently under study by the CMS collaboration using the first high-energy run of the LHC. These algorithms have been primarily developed and validated using simulated data samples, and are now being commissioned with LHC p-p collision data samples. The CMS reconstruction is now operated routinely on all events triggered by the CMS detector, both in a close to realtime prompt reconstruction processing and in frequent passes over the full recorded CMS data set. We discuss the overall software design, development cycle, computational requirements and performance, recent operational performance, and planned improvements of the CMS reconstruction software.