Project:Perl/5.22 Known Issues

>=sys-libs/zlib-1.2.9 breaks perl tests and niche uses of Compress::Raw::Zlib bug #606374, RT#119762

Packages needing upgrade

>=dev-perl/List-MoreUtils-0.402.0 (otherwise does not compile, RT#123479, stabilization in bug #565794, fixed 2015-12-26 14:51:48 UTC with dev-perl/List-MoreUtils-0.413.0)
>=dev-perl/Exporter-Tiny-0.42.0 (needed by List-MoreUtils, stabilization in bug #565794, fixed 2015-12-26 14:51:48 UTC)
>=dev-perl/PadWalker-2.100.0 (otherwise does not build, bug #552530, stabilization in bug #566938, fixed 2015-12-07 11:44:02 UTC with dev-perl/PadWalker-2.100.0)
>=app-shells/psh-1.8.1-r2 (otherwise broken install, bug #555178, fixed 2015-12-03 17:20:53 UTC with app-shells/psh-1.8.1-r2)
www-apache/mod_perl, causes apache to segfault if used with perl-5.22, bug #554794, fixed 2016-01-09 19:31:02 UTC with www-apache/mod_perl-2.0.8-r3)

media-gfx/graphviz (needs stabilization of an EAPI=5 version, bug #529462, fixed 2016-06-05 00:12:26 UTC with media-gfx/graphviz-2.38.0-r1)
net-fs/samba (missing perl dependency, bug #552800, fixed 2016-05-21 21:42:42 UTC)

 * Detected file collision(s):
 * 
 *      /usr/share/man/man1/encguess.1.bz2
 *      /usr/bin/encguess

(best ignore it and re-run emerge with FEATURES=protect-owned)

If the following code doesn't occupy any user time, similar to shown

time seq 0 100000000 >/dev/null

real    0m1.367s
user    0m0.000s
sys     0m1.009s

Then your kernel is doing time accounting wrong.

You might need any of the above reconfigured