Mobile Intel Celeron CPU? (/CFLAGS/GCC)

[OneInchMen]

What CFLAGS can I use for this processor?

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processor       : 0
vendor_id       : GenuineIntel
cpu family      : 15
model           : 2
model name      : Mobile Intel(R) Celeron(R) CPU 2.40GHz
stepping        : 9
cpu MHz         : 2394.031
cache size      : 256 KB
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 sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe cid xtpr
bogomips        : 4793.25

Based on the family/model numbering, I guess I can use the pentium4 architecture? -> gentoo-wiki

I plan to 'upgrade' my HP eVectra P3/1GHz/256MB home-server with a Toshiba SP Laptop with the above CPU. My P3 has these CFLAGS:

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CFLAGS="-mtune=pentium3 -march=pentium3 -Os -pipe -fomit-frame-pointer"
CXXFLAGS="${CFLAGS}"
LDFLAGS="-Wl,-O1 -Wl,--enable-new-dtags -Wl,--sort-common -Wl,--as-needed -s"
CHOST="i686-pc-linux-gnu"
MAKEOPTS="-j2"

* Can I reuse these CFLAGS (replacing pentium3 with pentium4) or are there any listed that shouldn't be there?
* Which version of GCC do you recommend as I'm planning to bootstrap the machine?

-tnx-

[Mickael]

Hello,

Killerwhile has written a little script in order to find the good USE parameter for a CPU :
http://forums.gentoo.org/viewtopic-t-45 ... while.html

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#!/bin/bash
for i in `grep flags /proc/cpuinfo | head -n 1 | cut -d":" -f2 | sed "s/dts//"`
do
    euse -i -g $i | grep -v searching | grep $i
done

Look here for your flags.

and if you want more information emerge this command x86info and try

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x86info -a

x86info -a
x86info v1.13. Dave Jones 2001-2003
Feedback to <davej@redhat.com>.

Need to be root to use specified options.
Found 1 CPU
--------------------------------------------------------------------------
eax in: 0x00000000, eax = 00000002 ebx = 756e6547 ecx = 6c65746e edx = 49656e69
eax in: 0x00000001, eax = 00000f27 ebx = 0001080e ecx = 00000000 edx = bfebfbff
eax in: 0x00000002, eax = 665b5101 ebx = 00000000 ecx = 00000000 edx = 007b7040

eax in: 0x80000000, eax = 80000004 ebx = 00000000 ecx = 00000000 edx = 00000000
eax in: 0x80000001, eax = 00000000 ebx = 00000000 ecx = 00000000 edx = 00000000
eax in: 0x80000002, eax = 4d202020 ebx = 6c69626f ecx = 6e492065 edx = 286c6574
eax in: 0x80000003, eax = 50202952 ebx = 69746e65 ecx = 52286d75 edx = 20342029
eax in: 0x80000004, eax = 204d202d ebx = 20555043 ecx = 30382e31 edx = 007a4847

Family: 15 Model: 2 Stepping: 7 Type: 0 Brand: 14
CPU Model: Pentium 4 (Northwood) [C1] Original OEM
Processor name string: Mobile Intel(R) Pentium(R) 4 - M CPU 1.80GHz

Feature flags:
fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflsh dtes acpi mmx fxsr sse sse2 selfsnoop ht acc pbe
Extended feature flags:

Instruction trace cache:
Size: 12K uOps 8-way associative.
L1 Data cache:
Size: 8KB Sectored, 4-way associative.
line size=64 bytes.
L2 unified cache:
Size: 512KB Sectored, 8-way associative.
line size=64 bytes.
Instruction TLB: 4K, 2MB or 4MB pages, fully associative, 128 entries.
Data TLB: 4KB or 4MB pages, fully associative, 64 entries.
The physical package supports 1 logical processors

Connector type: Socket478 (PGA478 Socket)

Datasheet: http://developer.intel.com/design/penti ... 988703.pdf
http://developer.intel.com/design/penti ... 864304.pdf
Errata: http://developer.intel.com/design/penti ... 249199.htm

1.8Ghz processor (estimate).

In root you will have more details.

[Mickael]

I don't know if you a "good" mother board or chipset with your CPU (see intel.com and use the x86info -a in root in order to complete the filter) maybe you can have the hyperthreading and in this case you must have the SMP module inside your kernel

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zgrep SMP /proc/config.gz
# CONFIG_X86_BIGSMP is not set
CONFIG_SMP=y
CONFIG_X86_FIND_SMP_CONFIG=y
CONFIG_X86_SMP=y

and make -j3 inside your make.conf

After that

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cat /proc/cpuinfo

will see 2 cpu!

[erikm]

I don't know if you a "good" mother board or chipset with your CPU (see intel.com and use the x86info -a in root in order to complete the filter) maybe you can have the hyperthreading and in this case you must have the SMP module inside your kernel

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zgrep SMP /proc/config.gz
# CONFIG_X86_BIGSMP is not set
CONFIG_SMP=y
CONFIG_X86_FIND_SMP_CONFIG=y
CONFIG_X86_SMP=y

and make -j3 inside your make.conf

After that

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cat /proc/cpuinfo

will see 2 cpu!

Just a quick addition: Hyperthreading is not SMP, and also needs the SMT scheduler to work. That is, the options you've posted should be set, but not without

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CONFIG_SCHED_SMT=y

Make -j3 sets the default parallel make option to three, which is recommended for two CPU:s. It is not necessary, however; you can set it to whatever you like.

[Mickael]

Thanks I will search if everything is OK for me. Thanks a lot Erik for your comment.

[chrismortimore]

http://gentoo-wiki.com/Cflags
and....
http://gentoo-wiki.com/Safe_Cflags

[OneInchMen]

I'm on a pre-bootstrap machine, so I don't have euse nor x86info...

My celeron seems to be the stripped P4 version, so I'll go with the -mtune=pentium4.

Although 'ht' is listed as cpu flag, it's highly unlikely the this celeron actually supports hyperthreading...

I've done some more reading on the --as-needed ldflag and I'm still undecided. The laptop will be a console only mail/dns/apache/dhcp/file/samba/etc server, so I might just go for the 'safer' cflags and ldflags...

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CFLAGS="-mtune=pentium4 -march=pentium4 -O2 -pipe -fomit-frame-pointer"
CXXFLAGS="${CFLAGS} -fvisibility-inlines-hidden"
LDFLAGS="-Wl,-O1 -Wl,--enable-new-dtags -Wl,--sort-common -W1, -s"
CHOST="i686-pc-linux-gnu"
MAKEOPTS="-j2"

Last but not least: I will be using the masked gcc 4.1.0...

(further investigating the --as-needed ldflag)

edit: typo's and cxxflag -fvisibility-inlines-hidden added

[chrismortimore]

Although 'ht' is listed as cpu flag, it's highly unlikely the this celeron actually supports hyperthreading...

According to this site: http://www.msicomputer.com/pressrelease/HT.asp some Celerons support HT, so it's worth trying it. And I realise its not the first place to look for Intel information, google gave me it

[OneInchMen]

SMP/HT: Tried, tested > /dev/null...

I don't recall exactly what the message was, but it was something like "SMP motherboard not installed" and "Hyperthreading disabled"...

The laptop is up and running now and completely (re)built with gcc-4.1.0 and --as-needed, with just one compiling problem to conquerer.

I'm happy with the performance of the celeron processor as I really thought that I should upgrade to a pentium4 or pentium-m.

Thanx for helping me out!