The innobackupex binary created by merging dev-db/percona-xtrabackup-2.4.4 requires the DBD::mysql perl-module to be installed, but the ebuild does not depend on it. Manually merging dev-perl/DBD-mysql and all its dependencies in their latest stable release fixed the problem. dev-db/xtrabackup-bin rdepends on dev-perl/DBD-mysql, dev-db/percona-xtrabackup does not, so I assume simply adding the line from the xtrabackup-bin ebuild to dev-db/percona-xtrabackup ebuilds should suffice to fix it. Reproducible: Always
(In reply to Felix Tiede from comment #0) Please attach 'emerge --info dev-db/percona-xtrabackup' output and the error message you see (if any) related to this missing dependency.
Created attachment 442580 [details] emerge --info dev-db/percona-xtrabackup
Created attachment 442582 [details] innobackupex error requesting DBD::mysql perl module. Seems to also work without this module, but innobackupex can not perform a version_check without it anymore. Seems to be not a vital check, but doesn't look good on a vital database backup if there are checks failing.
Thank you very much for the report, this should be fixed via https://github.com/gentoo/gentoo/pull/2008. Leaving open until it's merged.
The PR was merged, thanks for the report Felix.