Runtime measurements for each mapper dealing with real datasets. Runtime measurements are in minutes. The time measurements are the runtimes for when the indexing and mapping steps are considered together. Vertical bars show the user runtime (time elapsed during the experiments) and vertical lines indicate the CPU time. The time axis is in log scale. Each mapper was run with 24 threads (except Novoalign, SRmapper, SSAHA2, which were run with 1 thread). (1) indicates the mappers that report only one read (‘any-best’ mode) and (2) indicates the mappers that can run only in ‘all-best’ mode.