经验谈：如何使你的系统达到最优化？

哈蜜瓜

1、检查你的gcc版本：

#gcc --version

2、获取你的cpu的型号：

cat /proc/cpuinfo

3、在/etc/下建立make.conf文件，并根据cpu的型号写入不同内容。注意你的gcc版本必须在3.0以上。
i386 (Intel)：

CHOST="i386-pc-linux-gnu"
CFLAGS="-march=i386 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=i386 -O3 -pipe -fomit-frame-pointer"

i486 (Intel)：

CHOST="i486-pc-linux-gnu"
CFLAGS="-march=i486 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=i486 -O3 -pipe -fomit-frame-pointer"

Pentium 1 (Intel)

CHOST="i586-pc-linux-gnu"
CFLAGS="-march=pentium -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium -O3 -pipe -fomit-frame-pointer"

Pentium MMX (Intel)

CHOST="i586-pc-linux-gnu"
CFLAGS="-march=pentium-mmx -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium-mmx -O3 -pipe -fomit-frame-pointer"

Pentium PRO (Intel)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=pentiumpro -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentiumpro -O3 -pipe -fomit-frame-pointer"

Pentium II (Intel)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=pentium2 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium2 -O3 -pipe -fomit-frame-pointer"

Celeron (Mendocino), aka Celeron1 (Intel)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=pentium2 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium2 -O3 -pipe -fomit-frame-pointer"

Pentium III (Intel)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=pentium3 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium3 -O3 -pipe -fomit-frame-pointer"

Celeron (Coppermine) aka Celeron2 (Intel)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=pentium3 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium3 -O3 -pipe -fomit-frame-pointer"

Celeron (Willamette?) (Intel)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=pentium4 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium4 -O3 -pipe -fomit-frame-pointer"

Pentium 4 (Intel)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=pentium4 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium4 -O3 -pipe -fomit-frame-pointer"

Eden C3/Ezra (Via)

CHOST="i586-pc-linux-gnu"
CFLAGS="-march=i586 -m3dnow -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=i586 -m3dnow -O3 -pipe -fomit-frame-pointer"

K6 (AMD)

CHOST="i586-pc-linux-gnu"
CFLAGS="-march=k6 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=k6 -O3 -pipe -fomit-frame-pointer"

K6-2 (AMD)

CHOST="i586-pc-linux-gnu"
CFLAGS="-march=k6-2 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=k6-2 -O3 -pipe -fomit-frame-pointer"

K6-3 (AMD)

CHOST="i586-pc-linux-gnu"
CFLAGS="-march=k6-3 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=k6-3 -O3 -pipe -fomit-frame-pointer"

Athlon (AMD)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=athlon -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=athlon -O3 -pipe -fomit-frame-pointer"

Athlon-tbird, aka K7 (AMD)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=athlon-tbird -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=athlon-tbird -O3 -pipe -fomit-frame-pointer"

Athlon-tbird XP (AMD)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=athlon-xp -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=athlon-xp -O3 -pipe -fomit-frame-pointer"

Athlon 4(AMD)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=athlon-4 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=athlon-4 -O3 -pipe -fomit-frame-pointer"

Athlon XP (AMD)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=athlon-xp -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=athlon-xp -O3 -pipe -fomit-frame-pointer"

Athlon MP (AMD)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=athlon-mp -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=athlon-mp -O3 -pipe -fomit-frame-pointer"

603 (PowerPC)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-O3 -pipe -fsigned-char"
CXXFLAGS="-O3 -pipe -fsigned-char"

603e (PowerPC)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-O3 -pipe -fsigned-char"
CXXFLAGS="-O3 -pipe -fsigned-char"

604 (PowerPC)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-O3 -pipe -fsigned-char"
CXXFLAGS="-O3 -pipe -fsigned-char"

604e (PowerPC)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-O3 -pipe -fsigned-char"
CXXFLAGS="-O3 -pipe -fsigned-char"

750 aka as G3 (PowerPC)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-mcpu=750 -O3 -pipe -fsigned-char -mpowerpc-gfxopt"
CXXFLAGS="-mcpu=750 -O3 -pipe -fsigned-char -mpowerpc-gfxopt"

7400, aka G4 (PowerPC)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-mcpu=7400 -O2 -pipe -fsigned-char -maltivec
        -mabi=altivec -mpowerpc-gfxopt"
CXXFLAGS="-mcpu=7400 -O2 -pipe -fsigned-char -maltivec
        -mabi=altivec -mpowerpc-gfxopt"
   -fsigned-char -maltivec -mabi=altivec -mpowerpc-gfxopt"

7450, aka G4 second generation (PowerPC)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-mcpu=7450 -O2 -pipe -fsigned-char
        -maltivec -mabi=altivec -mpowerpc-gfxopt"
CXXFLAGS="-mcpu=7450 -O2 -pipe -fsigned-char
        -maltivec -mabi=altivec -mpowerpc-gfxopt"


PowerPC (If you don't know which one)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-O3 -pipe -fsigned-char -mpowerpc-gfxopt"
CXXFLAGS="-O3 -pipe -fsigned-char -mpowerpc-gfxopt"

Sparc

CHOST="sparc-unknown-linux-gnu"
CFLAGS="-O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-O3 -pipe -fomit-frame-pointer"

Sparc 64

CHOST="sparc64-unknown-linux-gnu"
CFLAGS="-O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-O3 -pipe -fomit-frame-pointer"


好了，这样做后你编译出的程序运行效率将比以前高很多！只要你有时间，你可以把你的系统如redhat linux 9.0的源代码（后缀.src.rpm）全部重新编译一次，你会发现你的Redhat Linux系统将比原来快一大截！
############################################################

以上我在RedHat Linux 9.0及Mandrake Linux 9.1上通过并证明有效。

狂客

Good!

wangli70

好！

chemist

为什么在我的 RH9 上不管用呢？编译 srpm 时，我看用的仍然是原来的优化选项 -O2

llw318

很棒!
试试看!

yuzheng

我用的是freebsd5.1,在cpu的设置时参考了
http://www.freebsd.org/releases/5.1R/relnotes-i386.html
文中有一段对p4的说明============================
GCC has been updated to 3.2.2 (release version).

    Note: GCC is known to produce broken code with the -march=pentium4 option set. As a workaround to avoid this problem, setting the CPUTYPE=p4 Makefile variable (for example, in make.conf(5)) enables GCC's -march=pentium3 option instead. This situation is expected to be resolved when GCC 3.3 is imported.
===============================================
我想gcc的用法都是一样的,建议大家对p4的cpu设置时要考虑一下.文中说的很明白了.

特务

哇，每个软件重新编译。。俺已经是没有rpm不能活了，怎么办？

Debentoo Gao

适合所有的Linux版本吗

franktom

好像在gentoo看到过，在其他系统也能用？会直接读取make.conf文件吗？

yufeng8552

我的CPU信息,没找到对应的，帮帮忙
[root@BillingServer root]# cat /proc/cpuinfo
processor       : 0
vendor_id       : GenuineIntel
cpu family      : 15
model           : 2
model name      : Intel(R) XEON(TM) CPU 1.80GHz
stepping        : 4
cpu MHz         : 1794.245
cache size      : 512 KB
physical id     : 0
siblings        : 2
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 2
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
bogomips        : 3578.26