Compression can take long time for highly parallel builds as it currently uses only one core. This is problematic especially for continuous integration of large projects that are built on hardware with many cores.

This feature, which is provided as a Technology Preview, enables multi-threaded xz compression for source and binary packages when setting the %_source_payload or %_binary_payload macros to the wLTX.xzdio pattern . In it, L represents the compression level, which is 6 by default, and X is the number of threads to be used (may be multiple digits), for example w6T12.xzdio. This can be done by editing the /usr/lib/rpm/macros file or by declaring the macro within the spec file or at the command line. (BZ#1278924)