Re: [gentoo-amd64] Please suggest settings and flags in /etc/make.conf?

[Lie Ryan]

On 01/22/10 11:44, Mark Knecht wrote:
> I'm just installing Gentoo on my first new machine in years. Can
> anyone suggest which of the CPU flags below might best be added to
> make.conf? The machine will be a standard desktop running rt-sources
> and stable Gentoo.
>
> This processor is 2 physical cores with hyperthreading enabled in each core.
>
> Currently make.conf has only the standard stuff other than me adding
> the MAKEOPTS line:
>
> # These settings were set by the catalyst build script that automatically
> # built this stage.
> # Please consult /usr/share/portage/config/make.conf.example for a more
> # detailed example.
>q CFLAGS="-O2 -pipe"
> CXXFLAGS="-O2 -pipe"

You might want to add "-march=" flag to CFLAGS and CXXFLAGS. See
http://en.gentoo-wiki.com/wiki/Safe_Cflags

> # WARNING: Changing your CHOST is not something that should be done lightly.
> # Please consult http://www.gentoo.org/doc/en/change-chost.xml before changing.
> CHOST="x86_64-pc-linux-gnu"

As the warning said, there is nearly no good reason to change CHOST.

> # These are the USE flags that were used in addition to what is provided by the
> # profile used for building.
> USE="mmx sse sse2"

No one size fits all, only you can decide the best USE flags combination
for your use. You probably wouldn't know the USE flags to use until you
emerged some programs. Before emerging, look at the USE flags and decide
whether you will need the feature activated by the flag, and whether you
want to activate the USE flags globally (add here) or locally for the
specific package (in /etc/portage/package.use).

You may want to look at /usr/portage/profiles/use.desc

> MAKEOPTS="-j5"



You might want to add your SYNC and GENTOO_MIRRORS options. Use the
mirrorselect program to choose the server to use.

If you're going to use GUI with X, you might want to add VIDEO_CARDS and
INPUT_DEVICES variable. Add the graphic and input driver you're using there.

Most emerges takes a long time; you most likely want to make portage a
low priority process so they does not disturb your daily work. Use
PORTAGE_NICENESS and PORTAGE_IONICE_COMMAND variable.

The FEATURES variable can set some useful optional portage features.
Look at "man make.conf" for valid options. Some options can speed up
compiling, others may increase security. Some of the most useful FEATURES:
- ccache: you'll need to emerge dev-utils/ccache and tune the CCACHE_SIZE
- parallel-fetch: the name describes best
- test: runs "make check" for packages that have them and fail the
install when the test don't pass. Be aware that quite a lot of package
is shipped with failed tests. You may want to add "--keep-going" when
emerging a large number of packages.
- userfetch, usersandbox, usersync: these may add a little bit of security.

See "man make.conf" for more options

>
>
> Thanks,
> Mark
>
>
> processor       : 3
> vendor_id       : GenuineIntel
> cpu family      : 6
> model           : 37
> model name      : Intel(R) Core(TM) i5 CPU         661  @ 3.33GHz
> stepping        : 2
> cpu MHz         : 3325.050
> cache size      : 4096 KB
> physical id     : 0
> siblings        : 4
> core id         : 2
> cpu cores       : 2
> apicid          : 5
> initial apicid  : 5
> fpu             : yes
> fpu_exception   : yes
> cpuid level     : 11
> wp              : yes
> flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
> mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe
> syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good
> xtopology nonstop_tsc pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2
> ssse3 cx16 xtpr pdcm sse4_1 sse4_2 aes lahf_lm ida tpr_shadow vnmi
> flexpriority ept vpid
> bogomips        : 6649.95
> clflush size    : 64
> cache_alignment : 64
> address sizes   : 36 bits physical, 48 bits virtual
> power management:
>