Zack Medico

In >=portage-2.2_rc2 there are a few new emerge options that many Gentoo users will probably be interested in:

--jobs JOBS
	Specifies the number of packages to build simultaneously.
	Also see the related --load-average option.

--keep-going
	Continue as much as possible after an error. When an error
	occurs, dependencies are recalculated for remaining packages
	and any with unsatisfied dependencies are automatically
	dropped. Also see the related --skipfirst option.

--load-average LOAD
	Specifies that no new builds should be started if there are
	other builds running and the load average is at least LOAD (a
	floating-point number). This option is recommended for use in
	combination with --jobs in order to avoid excess load. See
	make(1) for information about analogous options that should
	be configured via MAKEOPTS in make.conf(5).

Here is some sample parallel build output from a catalyst stage2 build, with emerge's new --jobs option enabled:

>>> Building (1 of 10) sys-devel/gettext-0.17 for /
>>> Building (2 of 10) sys-libs/zlib-1.2.3-r1 for /
>>> Building (3 of 10) virtual/libintl-0 for /
>>> Building (4 of 10) dev-util/unifdef-1.20 for /
>>> Installing virtual/libintl-0 to /
>>> Installing dev-util/unifdef-1.20 to /
>>> Building (5 of 10) sys-kernel/linux-headers-2.6.23-r3 for /
>>> Installing sys-libs/zlib-1.2.3-r1 to /
>>> Jobs: 3 of 10 complete, 2 running               Load avg: 3.44, 1.46, 0.69