Emerge times

To demystify the notion that it still takes hours to compile something in Gentoo, I leave here the times of the packages that take the most time on my machines.

Environments

Intel(R) Core(TM) i5-2500 CPU @ 3.30GHz
CFLAGS="-O2 -march=native -pipe"
MAKEOPTS="-j5"
EMERGE_DEFAULT_OPTS="--jobs=1 --quiet-build"
Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz
CFLAGS="-O2 -pipe -march=native"
MAKEOPTS="-j9"
EMERGE_DEFAULT_OPTS="--jobs=1 --quiet-build"

Both machines are using gcc 4.9.3, and the times are calculated with the script mergetime.awk, which only accounts for the real compile times given by the log, and not for time spent by the package manager in other tasks like downloading and extracting archives.

Times

Top 15 packages build times
PackageVersion i7-3770 i5-2500
app-office/libreoffice 5.1.4.2 1h 12m 44s 1h 32m 11s
sys-devel/gcc 4.9.3 22m 26s 27m 56s
dev-qt/qtwebkit 5.6.1 18m 57s 26m 48s
dev-qt/qtwebkit 4.8.6-r1 18m 28s 24m 10s
www-client/firefox 49.0 16m 46s 21m 18s
sys-devel/llvm 3.7.1-r3 15m 34s 22m 22s
dev-lang/mono 4.4.1.0 13m 58s 14m 44s
www-client/phantomjs 1.9.8 13m 01s
app-emulation/wine 1.8.3 9m 57s 14m 08s
media-gfx/inkscape 0.91-r3 6m 51s 9m 56s
sys-libs/glibc 2.22-r4 5m 20s 7m 31s
dev-qt/qtgui 4.8.6-r4 5m 18s 6m 08s
media-libs/mesa 12.0.1 5m 17s 11m 54s
dev-libs/boost 1.56.0-r1 5m 03s 5m 20s
x11-libs/wxGTK 3.0.2.0-r2 4m 49s 6m 41s

All packages information
i7-3770i5-2500
Data files linklink
Full rebuild time 9h 11m 32s 13h 15m 29s
Packages installed 11731351
Packages compiled in 10 seconds or less 777 - 66.24%823 - 60.92%
Packages compiled in 1 minute or less 1085 - 92.50%1222 - 90.45%
Packages compiled in 5 minutes or less 1157 - 98.64%1326 - 98.15%