Comment 5 for bug 1563784

lock elision is enabled by default on s390x, ppc64el, amd64 on Ubuntu.

Note that s390x port of Ubuntu _only_ targets zEC12 and up, thus we can rely on TX (Hardware Transactional Execution / Transacational Memory) to be available.

This is inline with other distributions too, e.g. fedora and opensuse both build with lock elision enabled by default.

http://s390.koji.fedoraproject.org/kojifiles/packages/glibc/2.23.90/2.fc25/data/logs/s390x/build.log

https://build.opensuse.org/package/live_build_log/openSUSE:Factory:zSystems/glibc/standard/s390x

glibc upload has been validated through a full archive rebuild (see announcement on https://lists.ubuntu.com/archives/ubuntu-devel-announce/2016-April/001178.html ) and autopkgtest suites for integration testing.

Disabling lock elision at this point of release cycle could only be realistic driven by publicly known hardware issues of shipped zEC12 or later z Systems. Are there any publicly disclosed hardware issues with TX that release team needs to be aware of?