[gentoo-user] Re: Simultaneously emerging multiple packages with same dependencies

[Nikos Chantziaras <realnc@arcor.de>]

On 01/27/2011 04:16 PM, Neil Bothwick wrote:
> On Thu, 27 Jan 2011 15:33:21 +0200, Nikos Chantziaras wrote:
>
>>> I am using the -j option for the first time now. I'm updating KDE. It
>>> seems to work fine. It doesn't scroll all the stuff like with a
>>> regular emerges but this new rig is so fast, I can't read it anyway.
>>> I did have a package to fail and it spit out the error for me to
>>> read.
>>
>> You don't need that if you have MAKEOPTS set in your make.conf, which
>> is preferred.  The -j option of emerge emerges multiple packages, while
>> with MAKEOPTS set to "-j4" or whatever does a parallel build in the
>> same package (meaning compiling multiple source files at the same time).
>
> And how many CPU cores are used during the configure and install stages?
>
> Using --jobs does a better job of making use of your CPU because one
> package can use it fully for compiling while another is configuring.

And what about the last package?  The time you gained for faster 
configure and install (which don't take too much time anyway) is wasted 
again on the last package.