which best CFLAGS & MAKEOPTS for 'Intel Core Duo T2700'

ge3kz · n00b Joined: 16 Aug 2011 Posts: 4

Hello,

i want install Gentoo latest version, so what is best CFLAGS for my processor 'Intel Core Duo T2700'.

also what is best value for MAKEOPTS

MAKEOPTS="-j2" or MAKEOPTS="-j3"

more information about hardware:
cpu: Intel Core Duo T2700
ram : 2GB
crad graphical : ATI Radeon 2400 PRO.
sound: Creative Blaster.

Thank you advance.

BradN · Posted: Tue Aug 16, 2011 10:26 pm Post subject:

I'm too lazy to look up -march names for that CPU...

But, for MAKEOPTS, -j# says how many compilation threads to run at a time, I suggest just doing your number of processor cores there. There may be a slight gain by increasing it to 1+# of cpu cores, but probably not much. Keep in mind compile time memory requirements will increase as the number of threads is increased, so if you regularly use a lot of your 2GB, using a large number of compile threads might hurt performance for your other applications while you compile.

Jaglover · Posted: Tue Aug 16, 2011 10:34 pm Post subject:

Welcome to Gentoo!

march=native is a safe and good choice. Enable sse* USE flags for packages that support/need it.

As for threads, it's up to you. I use -j3 on my quadcore just to keep it responsive while compiling.
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d2_racing · Posted: Wed Aug 17, 2011 12:14 pm Post subject:

On my box I use -march=native and I use -j5 for a Quad Core Q9550.

aCOSwt · Posted: Wed Aug 17, 2011 2:17 pm Post subject:

If you experiment faster builds with -jN and N greater than the number of logical cores then... :
Change your scheduler !

Hans-Linux · Posted: Wed Aug 24, 2011 12:28 pm Post subject:

I use CFLAGS="-march=native -mtune-native -O3" and MAKEOPTS="-j5" on a 3 GHz quad core AMD Phenom in a VirtualBox with 2GB RAM.

mark_alec · Posted: Wed Aug 24, 2011 12:46 pm Post subject:

BradN · Posted: Thu Sep 01, 2011 11:20 pm Post subject:

-O2 and -O3 are pretty close in terms of safeness but it's kinda a crapshoot which will produce better performing code. -O3 enables everything -O2 does plus optimizations that increase code size. Sometimes the effect this has on cache memory negates the benefit or even makes it worse.

solamour · Posted: Fri Sep 02, 2011 1:24 am Post subject:

I believe "Core Duo T2700" is a 32-bit processor, so something like the following should work.