Mailing List Archive

I've got a Blueberry iBook, with a 300 MHz ppc, and these seem very
stable to me:

CFLAGS="-O2 -mtune=G3 -pipe"

-Drew


On Sat, 19 Feb 2005 21:40:28 -0500 (EST), Nick Smith
<nick@computernick.com> wrote:
> can someone point me to a list of cflags that are compatible
> with PPC? i found some but it doesnt say if they are PPC
> specific or not, cause that was the problem with my boot strap
> it didnt like -march=powerpc or -ftracer and i would like to
> know exactly what i can use with this new hardware. G3 350Mhz.
>
> thanks
> --
> Nick Smith a.k.a. Computer Nick
> Web - http://www.computernick.com
> Email - Nick@ComputerNick.com
> --
>
> --
> gentoo-ppc-user@gentoo.org mailing list
>
>

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<quote who="Drew Kirkpatrick">
> I've got a Blueberry iBook, with a 300 MHz ppc, and these seem
> very
> stable to me:
>
> CFLAGS="-O2 -mtune=G3 -pipe"

well the default file that game with the install has:
CFLAGS="-02 -mtune=powerpc -fno-strict-aliasing -pipe"
i was just tring to add some more and it puked, do you know what
the differences are between the G3 and powerpc flags? what
should i be using? is one better that the other?

thanks
>
> -Drew
>
>
> On Sat, 19 Feb 2005 21:40:28 -0500 (EST), Nick Smith
> <nick@computernick.com> wrote:
>> can someone point me to a list of cflags that are compatible
>> with PPC? i found some but it doesnt say if they are PPC
>> specific or not, cause that was the problem with my boot strap
>> it didnt like -march=powerpc or -ftracer and i would like to
>> know exactly what i can use with this new hardware. G3 350Mhz.
>>
>> thanks
>> --
>> Nick Smith a.k.a. Computer Nick
>> Web - http://www.computernick.com
>> Email - Nick@ComputerNick.com
>> --
>>
>> --
>> gentoo-ppc-user@gentoo.org mailing list
>>
>>
>
> --
> gentoo-ppc-user@gentoo.org mailing list
>
>



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On Sat February 19 2005 21:49, Nick Smith wrote:

> <quote who="Drew Kirkpatrick">
>
> > I've got a Blueberry iBook, with a 300 MHz ppc, and these seem
> > very
> > stable to me:
> >
> > CFLAGS="-O2 -mtune=G3 -pipe"

> well the default file that game with the install has:
> CFLAGS="-02 -mtune=powerpc -fno-strict-aliasing -pipe"

(Note that your "-O2" needs to contain a letter O, not a number zero, as you
have typed above... otherwise, I'm sure it will puke.)

> i was just tring to add some more and it puked, do you know what
> the differences are between the G3 and powerpc flags? what
> should i be using? is one better that the other?

Here on a 450 MHz G3, I've been using these flags for many months with no
problems:

CFLAGS="-O3 -mcpu=G3 -maltivec -mabi=altivec -fno-strict-aliasing -pipe"

As to the difference between G3 and powerpc, G3 is a subset of the larger
category, powerpc. PPC machines are made by Apple, IBM, and others; G3 is a
very specific version, among the processors that implement the PowerPC
instruction set. So, by specifying G3, we are telling the compiler exactly
what kind of CPU we have, so that it can enable any processor-specific
performance enhancements.

I mostly found the information on CFLAGS from the GCC documentation. You can
view the GCC info pages to find it, and if you use KDE you can paste these
into Konqueror to go directly to the relevant sections:

info:/gcc/Optimize Options
info:/gcc/RS/6000 and PowerPC Options

Good luck!

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//
// ==] What would Jeeves do? [==
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No idea to be honest with ya. I did have different CFLAGS at one
point, but would get internal compiler errors frequently, so I went
back to this and haven't had any problems since.


On Sat, 19 Feb 2005 21:49:12 -0500 (EST), Nick Smith
<nick@computernick.com> wrote:
> <quote who="Drew Kirkpatrick">
> > I've got a Blueberry iBook, with a 300 MHz ppc, and these seem
> > very
> > stable to me:
> >
> > CFLAGS="-O2 -mtune=G3 -pipe"
>
> well the default file that game with the install has:
> CFLAGS="-02 -mtune=powerpc -fno-strict-aliasing -pipe"
> i was just tring to add some more and it puked, do you know what
> the differences are between the G3 and powerpc flags? what
> should i be using? is one better that the other?
>
> thanks
> >
> > -Drew
> >
> >
> > On Sat, 19 Feb 2005 21:40:28 -0500 (EST), Nick Smith
> > <nick@computernick.com> wrote:
> >> can someone point me to a list of cflags that are compatible
> >> with PPC? i found some but it doesnt say if they are PPC
> >> specific or not, cause that was the problem with my boot strap
> >> it didnt like -march=powerpc or -ftracer and i would like to
> >> know exactly what i can use with this new hardware. G3 350Mhz.
> >>
> >> thanks
> >> --
> >> Nick Smith a.k.a. Computer Nick
> >> Web - http://www.computernick.com
> >> Email - Nick@ComputerNick.com
> >> --
> >>
> >> --
> >> gentoo-ppc-user@gentoo.org mailing list
> >>
> >>
> >
> > --
> > gentoo-ppc-user@gentoo.org mailing list
> >
> >
>
> --
> gentoo-ppc-user@gentoo.org mailing list
>
>

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On Sat February 19 2005 10:18 pm, Carl Hudkins wrote:
> On Sat February 19 2005 21:49, Nick Smith wrote:
>
> Here on a 450 MHz G3, I've been using these flags for many months with no
> problems:
>
> CFLAGS="-O3 -mcpu=G3 -maltivec -mabi=altivec -fno-strict-aliasing -pipe"
>

Does the G3 have altivec extensions? I thought that they didn't show up till
the G4.

Erik

<quote who="Erik Zeek">
> On Sat February 19 2005 10:18 pm, Carl Hudkins wrote:
>> On Sat February 19 2005 21:49, Nick Smith wrote:
>>
>> Here on a 450 MHz G3, I've been using these flags for many
>> months with no
>> problems:
>>
>> CFLAGS="-O3 -mcpu=G3 -maltivec -mabi=altivec
>> -fno-strict-aliasing -pipe"
>>
>
> Does the G3 have altivec extensions? I thought that they didn't
> show up till
> the G4.
man dont tell me that! i was going with what the guy said and
have almost completed the entire bootstrap with those cflags! i
hope your wrong.....(no offense of course)
>
> Erik
>
>



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On Sun February 20 2005 11:41 am, Nick Smith wrote:
> <quote who="Erik Zeek">
>
> > On Sat February 19 2005 10:18 pm, Carl Hudkins wrote:
> >> On Sat February 19 2005 21:49, Nick Smith wrote:
> >>
> >> Here on a 450 MHz G3, I've been using these flags for many
> >> months with no
> >> problems:
> >>
> >> CFLAGS="-O3 -mcpu=G3 -maltivec -mabi=altivec
> >> -fno-strict-aliasing -pipe"
> >
> > Does the G3 have altivec extensions? I thought that they didn't
> > show up till
> > the G4.
>
> man dont tell me that! i was going with what the guy said and
> have almost completed the entire bootstrap with those cflags! i
> hope your wrong.....(no offense of course)
>
> > Erik
>

If I recall correctly, it won't kill any thing. It might slow somethings
down. I just don't know for sure. The -mabi might cause problems with
compatibly with precompiled modules.

The best thing would be to look it up. I'm no expert on the PPC, but I
believe that I am correct in this.

Erik

According to PowerLogix:

Remember, the only difference between a G3 and a G4 is Altivec. Altivec
is a specialized vector processor and only a small number of specific
software tasks in some applications actually utilize it. The majority
of mainstream applications do not take advantage of Altivec. Even the
Darwin kernel, at the heart of Mac OS X, is not optimized to use
Altivec.

J_

Jeffrey M. Miller CISSP CISM RHCE CCNA LPIC-2
Sr. Security Consultant
Acumen InfoSec LLC
______________________
CONFIDENTIALITY NOTICE: This email message, including any attachments,
is for the sole use of the intended recipient(s) and may contain
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On Feb 20, 2005, at 11:48 AM, Erik Zeek wrote:

> On Sun February 20 2005 11:41 am, Nick Smith wrote:
>> <quote who="Erik Zeek">
>>
>>> On Sat February 19 2005 10:18 pm, Carl Hudkins wrote:
>>>> On Sat February 19 2005 21:49, Nick Smith wrote:
>>>>
>>>> Here on a 450 MHz G3, I've been using these flags for many
>>>> months with no
>>>> problems:
>>>>
>>>> CFLAGS="-O3 -mcpu=G3 -maltivec -mabi=altivec
>>>> -fno-strict-aliasing -pipe"
>>>
>>> Does the G3 have altivec extensions? I thought that they didn't
>>> show up till
>>> the G4.
>>
>> man dont tell me that! i was going with what the guy said and
>> have almost completed the entire bootstrap with those cflags! i
>> hope your wrong.....(no offense of course)
>>
>>> Erik
>>
>
> If I recall correctly, it won't kill any thing. It might slow
> somethings
> down. I just don't know for sure. The -mabi might cause problems with
> compatibly with precompiled modules.
>
> The best thing would be to look it up. I'm no expert on the PPC, but I
> believe that I am correct in this.
>
> Erik

Hello

> > Does the G3 have altivec extensions? I thought that they didn't
> > show up till the G4.

> i hope your wrong.....(no offense of course)

He's right. Only G4 and G5 have Altivec.

Greets,
Michael

--
Gentoo Developer (PowerPC, MacOS) using m0n0wall | http://hansmi.ch/
But that looks a little too much like a declaration for my tastes, when
in fact it isn't one. So forget I mentioned it.
-- Larry Wall in <199710011704.KAA21395@wall.org>

On Sun February 20 2005 13:06, Michael Hanselmann wrote:

> > > Does the G3 have altivec extensions? I thought that they didn't
> > > show up till the G4.
> >
> > i hope your wrong.....(no offense of course)
>
> He's right. Only G4 and G5 have Altivec.

Hm. I didn't look into the Altivec thing much further than /proc/cpuinfo,
which says:

processor : 0
cpu : 7400, altivec supported
temperature : 15-17 C (uncalibrated)
clock : 450MHz
revision : 2.9 (pvr 000c 0209)
bogomips : 894.97

processor : 1
cpu : 7400, altivec supported
temperature : 31-33 C (uncalibrated)
clock : 450MHz
revision : 2.9 (pvr 000c 0209)
bogomips : 894.97

total bogomips : 1789.95
machine : PowerMac3,3
motherboard : PowerMac3,3 MacRISC Power Macintosh
detected as : 65 (PowerMac G4 AGP Graphics)
pmac flags : 00000004
L2 cache : 1024K unified
memory : 256MB
pmac-generation : NewWorld

All this time I've been thinking it was a G3-based system... does this mean
it's actually a G4? You've gotta be kidding... :-p

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On Sun February 20 2005 01:26 pm, Carl Hudkins wrote:
> Hm. I didn't look into the Altivec thing much further than /proc/cpuinfo,
> which says:
>
> processor : 0
> cpu : 7400, altivec supported
> temperature : 15-17 C (uncalibrated)
> clock : 450MHz
> revision : 2.9 (pvr 000c 0209)
> bogomips : 894.97
>
> processor : 1
> cpu : 7400, altivec supported
> temperature : 31-33 C (uncalibrated)
> clock : 450MHz
> revision : 2.9 (pvr 000c 0209)
> bogomips : 894.97
>
> total bogomips : 1789.95
> machine : PowerMac3,3
> motherboard : PowerMac3,3 MacRISC Power Macintosh

> detected as : 65 (PowerMac G4 AGP Graphics)

Looks like it.

> pmac flags : 00000004
> L2 cache : 1024K unified
> memory : 256MB
> pmac-generation : NewWorld
>
> All this time I've been thinking it was a G3-based system... does this
> mean it's actually a G4? You've gotta be kidding... :-p

--
*******************************************
Dr. Erik Zeek
Postdoctoral Research Associate
Department of Physics and Astronomy
The University of Georgia
Athens, GA 30602-2451

Tel: 706-542-7293
Email: mailto:zeekec@mad.scientist.com
Html: http://www.physast.uga.edu/~zeekec
*******************************************
Against stupidity the very gods
Themselves contend in vain.
- Johann Christoph Friedrich von Schiller (1801)
*******************************************

<quote who="Erik Zeek">
> On Sun February 20 2005 01:26 pm, Carl Hudkins wrote:
>> Hm. I didn't look into the Altivec thing much further than
>> /proc/cpuinfo,
>> which says:
>>
>> processor : 0
>> cpu : 7400, altivec supported
>> temperature : 15-17 C (uncalibrated)
>> clock : 450MHz
>> revision : 2.9 (pvr 000c 0209)
>> bogomips : 894.97
>>
>> processor : 1
>> cpu : 7400, altivec supported
>> temperature : 31-33 C (uncalibrated)
>> clock : 450MHz
>> revision : 2.9 (pvr 000c 0209)
>> bogomips : 894.97
>>
>> total bogomips : 1789.95
>> machine : PowerMac3,3
>> motherboard : PowerMac3,3 MacRISC Power Macintosh
>
>> detected as : 65 (PowerMac G4 AGP Graphics)
>
> Looks like it.
well when this bootstrap finishes i see if im that lucky too ;-)
>
>> pmac flags : 00000004
>> L2 cache : 1024K unified
>> memory : 256MB
>> pmac-generation : NewWorld
>>
>> All this time I've been thinking it was a G3-based system...
>> does this
>> mean it's actually a G4? You've gotta be kidding... :-p
>
> --
> *******************************************
> Dr. Erik Zeek
> Postdoctoral Research Associate
> Department of Physics and Astronomy
> The University of Georgia
> Athens, GA 30602-2451
>
> Tel: 706-542-7293
> Email: mailto:zeekec@mad.scientist.com
> Html: http://www.physast.uga.edu/~zeekec
> *******************************************
> Against stupidity the very gods
> Themselves contend in vain.
> - Johann Christoph Friedrich von Schiller (1801)
> *******************************************
>



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[dom 20/02/2005, ore 13:26] => Carl Hudkins scriveva:

>
> processor : 0
> cpu : 7400, altivec supported
> temperature : 15-17 C (uncalibrated)
> clock : 450MHz
> revision : 2.9 (pvr 000c 0209)
> bogomips : 894.97
^^^^^^^^^^^^^^^^^^^^^^^^^

hey, wait a minute!
how comes that you have 895 bogomips with a 450Mhz G3?
this is my cpuinfo, i have a 1Ghz Powerbook G4 and all I get is
664 Bogomips!

processor : 0
cpu : 7447/7457, altivec supported
clock : 998MHz
revision : 1.1 (pvr 8002 0101)
bogomips : 664.20
machine : PowerBook6,2
motherboard : PowerBook6,2 MacRISC3 Power Macintosh
detected as : 287 (PowerBook G4)
pmac flags : 0000000a
L2 cache : 512K unified
memory : 512MB
pmac-generation : NewWorld




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On Feb 20, 2005, at 11:01 AM, hjk wrote:

> [dom 20/02/2005, ore 13:26] => Carl Hudkins scriveva:
>
>>
>> processor : 0
>> cpu : 7400, altivec supported
>> temperature : 15-17 C (uncalibrated)
>> clock : 450MHz
>> revision : 2.9 (pvr 000c 0209)
>> bogomips : 894.97
> ^^^^^^^^^^^^^^^^^^^^^^^^^
>
> hey, wait a minute!
> how comes that you have 895 bogomips with a 450Mhz G3?
> this is my cpuinfo, i have a 1Ghz Powerbook G4 and all I get is
> 664 Bogomips!

perhaps you are running in reduced cpu performance mode (battery power)?

check the gentoo ppc faq for 'cpu scaling'--you can set cpu speed via
/proc/cpufreq.
http://www.gentoo.org/doc/en/gentoo-ppc-faq.xml

john


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On Sun February 20 2005 14:01, hjk wrote:

> [dom 20/02/2005, ore 13:26] => Carl Hudkins scriveva:
> > processor : 0
> > cpu : 7400, altivec supported
> > temperature : 15-17 C (uncalibrated)
> > clock : 450MHz
> > revision : 2.9 (pvr 000c 0209)
> > bogomips : 894.97
>
> ^^^^^^^^^^^^^^^^^^^^^^^^^
>
> hey, wait a minute!
> how comes that you have 895 bogomips with a 450Mhz G3?
> this is my cpuinfo, i have a 1Ghz Powerbook G4 and all I get is
> 664 Bogomips!

Well, I just discovered it's really a G4... so that probably makes a
difference. I don't know how "bogomips" is calculated, so maybe something
else about your CPU, motherboard, or kernel is affecting it.

Hm... http://www.clifton.nl/ seems to indicate that bogomips is directly
proportional to clock speed for PPC machines, so maybe it's something about
the fact that you're running on a laptop. Is there some kind of "reduced
power" mode that makes it run at half-speed, for example? I'm just guessing
here. :)

Aha... Google found some info for me, which leads back to the kernel. It
seems the default speed on PowerBooks is about 2/3 of maximum, probably in
order not to make the thing extremely hot and such. If you're trying to
squeeze every bit of power out of your PowerBook, you may need to enable CPU
frequency scaling in the kernel. Check
out /usr/src/linux/Documentation/cpu-freq/user-guide.txt -- there are
different policies you may use to change how and when the frequency and/or
voltage changes.

Note that I have not used this... probably some folks on this list have,
though. I see someone has come up with the Gentoo FAQ for this, in fact. :)
I'm going to leave the rest to the experts now.

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<quote who="jkw">
>
> On Feb 20, 2005, at 11:01 AM, hjk wrote:
>
>> [dom 20/02/2005, ore 13:26] => Carl Hudkins scriveva:
>>
>>>
>>> processor : 0
>>> cpu : 7400, altivec supported
>>> temperature : 15-17 C (uncalibrated)
>>> clock : 450MHz
>>> revision : 2.9 (pvr 000c 0209)
>>> bogomips : 894.97
>> ^^^^^^^^^^^^^^^^^^^^^^^^^
>>
>> hey, wait a minute!
>> how comes that you have 895 bogomips with a 450Mhz G3?
>> this is my cpuinfo, i have a 1Ghz Powerbook G4 and all I get
>> is
>> 664 Bogomips!

i am getting 696.32 on my G3 350Mhz off the boot cd during the
install. (whatever Bogomips are?)

>
> perhaps you are running in reduced cpu performance mode (battery
> power)?
>
> check the gentoo ppc faq for 'cpu scaling'--you can set cpu
> speed via
> /proc/cpufreq.
> http://www.gentoo.org/doc/en/gentoo-ppc-faq.xml
>
> john
>
>
> --
> gentoo-ppc-user@gentoo.org mailing list
>
>



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[dom 20/02/2005, ore 16:25] => David Bélanger scriveva:

> On Sun, Feb 20, 2005 at 03:55:58PM -0500, Nick Smith wrote:
> >
> > i am getting 696.32 on my G3 350Mhz off the boot cd during the
> > install. (whatever Bogomips are?)
> >
>
> It's only a value computed by the kernel that has some purposes in the
> kernel. It gets print for "fun" but should not be regarded as a
> performance measure.
>

yes, i don't regard it as a performance measure, yet i am curious about the
reason why i get so few bogomips :)

i'm using a 2.6 kernel with sysfs, i have the "performance" governor enabled in
/sys/devices/system/cpu/cpu0/cpufreq/scaling_governor and my cpu is running
at 998.400 Mhz as stated in /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq

Mah.

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On Sun, Feb 20, 2005 at 03:55:58PM -0500, Nick Smith wrote:
>
> i am getting 696.32 on my G3 350Mhz off the boot cd during the
> install. (whatever Bogomips are?)
>

It's only a value computed by the kernel that has some purposes in the
kernel. It gets print for "fun" but should not be regarded as a
performance measure.

David

---

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Public key: http://www.cs.mcgill.ca/~dbelan2/public_key.txt


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On Sat, Feb 19, 2005 at 09:40:28PM -0500, Nick Smith wrote:
> can someone point me to a list of cflags that are compatible
> with PPC? i found some but it doesnt say if they are PPC
> specific or not, cause that was the problem with my boot strap
> it didnt like -march=powerpc or -ftracer and i would like to
> know exactly what i can use with this new hardware. G3 350Mhz.
>

Hi,

Try:
-O2 -mcpu=750 -pipe

I use:
-O3 -mcpu=750 -pipe
(Note: -O3 might improve or decrease performance but is stable).

About:
-fno-strict-aliasing
This strict-aliasing is enabled by default in -O2, meaning that apps where
it causes problem should disable it.

If you want to be on the safe side, then you can disable it all the
time but I don't do it.

David

---

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Web page: http://www.cs.mcgill.ca/~dbelan2/
Public key: http://www.cs.mcgill.ca/~dbelan2/public_key.txt


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On Sun, Feb 20, 2005 at 10:19:07PM +0100, hjk wrote:
> [dom 20/02/2005, ore 16:25] => David Bélanger scriveva:
>
> > On Sun, Feb 20, 2005 at 03:55:58PM -0500, Nick Smith wrote:
> > >
> > > i am getting 696.32 on my G3 350Mhz off the boot cd during the
> > > install. (whatever Bogomips are?)
> > >
> >
> > It's only a value computed by the kernel that has some purposes in the
> > kernel. It gets print for "fun" but should not be regarded as a
> > performance measure.
> >
>
> yes, i don't regard it as a performance measure, yet i am curious about the
> reason why i get so few bogomips :)
>
> i'm using a 2.6 kernel with sysfs, i have the "performance" governor enabled in
> /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor and my cpu is running
> at 998.400 Mhz as stated in /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
>

It's for timing purposes:
http://www.tldp.org/HOWTO/BogoMips/x78.html#AEN81

G3 = 750 - clock cycle * 2.0. Is your CPU clocked as 350MHz or
1000MHz... If at 350MHz, 696 is pretty close to the 700 BogoMIPS should
have.

David

---

David Bélanger
Web page: http://www.cs.mcgill.ca/~dbelan2/
Public key: http://www.cs.mcgill.ca/~dbelan2/public_key.txt


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"Nick Smith" writes:
|
| >>
| >> CFLAGS="-O3 -mcpu=G3 -maltivec -mabi=altivec
| >> -fno-strict-aliasing -pipe"
| >
| > Does the G3 have altivec extensions? I thought that they didn't
| > show up till
| > the G4.
| man dont tell me that! i was going with what the guy said and
| have almost completed the entire bootstrap with those cflags! i
| hope your wrong.....(no offense of course)



It's at this stage that Id like to re-suggest that we consider
collecting a table of cflags and put in in the install or ppc docs.
Something like table with a sample line from /proc/cpuinfo and then
the stable and risky CFLAGS settings.



For my G5 (no bogomips entry?):
CFLAGS="-O2 -mcpu=G5 -pipe -maltivec -mabi=altivec -fno-strict-aliasing -mpowerpc-gfxopt -mmultiple -mstring"


For my 800Mhz G3 laptop (1589.24 bogomips by the way:):
CFLAGS="-O2 -pipe -mcpu=750 -mpowerpc-gfxopt -mmultiple -mstring"



A while ago I was md5sum'ing some iso images and I noticed my G5
was _WAY_ slower than my G3 laptop and it was because Id dropped
the mcpu=G5 setting from my G5 CFLAGS. I realise that md5sum'ing is a
special case, but small changes can make a massive change.

Even if the idea is too hard for gentoo as a whole, would it be
possible for gentoo-ppc?


Ive suggested it a few times in posts like:

http://forums.gentoo.org/viewtopic-t-166999-highlight-.html

but everyone seems to say that its too hard :-/ or that there are too
many combos to track (which I dont quite get, I mean gentoo runs on
what, a couple of hundred cpu variations? Wouldnt the pain that this
solves be worth it? :)

I mean developers and iso releasers must work this stuff out.... :)
But I guess it would be harder in that one would need to collect the info
for cpu model and gcc version or maybe 'gentoo/portage version' too.

Id comment that once we had the data, creating a script on the install
disk wouldnt be hard, but Im sure that would take away a little more
of the 'hacker' spirit of the whole install process :-)


cheers,
cam

--
/ `Rev Dr' cam at darkqueen.org Roleplaying, virtual goth \
< http://darkqueen.org Poly, *nix, Python, C/C++, genetics, ATM >
\ [+61 3] 9809 1523[h] skeptic, Evil GM(tm). Sysadmin for hire /
---------- Random Quote ----------
Don't kiss an elephant on the lips today.

--
gentoo-ppc-user@gentoo.org mailing list

On my new 12" Aluminum PowerBook, I'm using the following with no
problems (results in spankin-fast binaries, too):

CFLAGS="-O2 -pipe -mcpu=7450 -maltivec -mabi=altivec -mpowerpc-gfxopt
-fsigned-char -mstring -mmultiple"
CHOST="powerpc-unknown-linux-gnu"
CXXFLAGS="${CFLAGS}"
MAKEOPTS="-j3"

chris.

:: Christopher Gautam Hota
:: Information Technology Specialist
:: MidSOUTH at UALR
:: cghota@midsouth.ualr.edu
:: (501) 683-7339 desk
:: (501) 413-1176 cell

|| Microsoft Certified Systems Engineer
|| Windows XP / Server 2003



Carl Hudkins wrote:

>On Sat February 19 2005 21:49, Nick Smith wrote:
>
>
>
>><quote who="Drew Kirkpatrick">
>>
>>
>>
>>>I've got a Blueberry iBook, with a 300 MHz ppc, and these seem
>>>very
>>>stable to me:
>>>
>>>CFLAGS="-O2 -mtune=G3 -pipe"
>>>
>>>
>
>
>
>>well the default file that game with the install has:
>>CFLAGS="-02 -mtune=powerpc -fno-strict-aliasing -pipe"
>>
>>
>
> (Note that your "-O2" needs to contain a letter O, not a number zero, as you
>have typed above... otherwise, I'm sure it will puke.)
>
>
>
>>i was just tring to add some more and it puked, do you know what
>>the differences are between the G3 and powerpc flags? what
>>should i be using? is one better that the other?
>>
>>
>
> Here on a 450 MHz G3, I've been using these flags for many months with no
>problems:
>
>CFLAGS="-O3 -mcpu=G3 -maltivec -mabi=altivec -fno-strict-aliasing -pipe"
>
> As to the difference between G3 and powerpc, G3 is a subset of the larger
>category, powerpc. PPC machines are made by Apple, IBM, and others; G3 is a
>very specific version, among the processors that implement the PowerPC
>instruction set. So, by specifying G3, we are telling the compiler exactly
>what kind of CPU we have, so that it can enable any processor-specific
>performance enhancements.
>
> I mostly found the information on CFLAGS from the GCC documentation. You can
>view the GCC info pages to find it, and if you use KDE you can paste these
>into Konqueror to go directly to the relevant sections:
>
>info:/gcc/Optimize Options
>info:/gcc/RS/6000 and PowerPC Options
>
> Good luck!
>
>
>

On Sun February 20 2005 07:41 pm, Cameron Blackwood wrote:
> It's at this stage that Id like to re-suggest that we consider
> collecting a table of cflags and put in in the install or ppc docs.
> Something like table with a sample line from /proc/cpuinfo and then
> the stable and risky CFLAGS settings.
>

You might check out:
http://gentoo-wiki.com/Safe_Cflags

You could start your own page, and start collecting the data.

>
> For my G5 (no bogomips entry?):
> CFLAGS="-O2 -mcpu=G5 -pipe -maltivec -mabi=altivec -fno-strict-aliasing
> -mpowerpc-gfxopt -mmultiple -mstring"
>
>
> For my 800Mhz G3 laptop (1589.24 bogomips by the way:):
> CFLAGS="-O2 -pipe -mcpu=750 -mpowerpc-gfxopt -mmultiple -mstring"
>
>
>
> A while ago I was md5sum'ing some iso images and I noticed my G5
> was _WAY_ slower than my G3 laptop and it was because Id dropped
> the mcpu=G5 setting from my G5 CFLAGS. I realise that md5sum'ing is a
> special case, but small changes can make a massive change.
>
> Even if the idea is too hard for gentoo as a whole, would it be
> possible for gentoo-ppc?
>
>
> Ive suggested it a few times in posts like:
>
> http://forums.gentoo.org/viewtopic-t-166999-highlight-.html
>
> but everyone seems to say that its too hard :-/ or that there are too
> many combos to track (which I dont quite get, I mean gentoo runs on
> what, a couple of hundred cpu variations? Wouldnt the pain that this
> solves be worth it? :)
>
> I mean developers and iso releasers must work this stuff out.... :)
> But I guess it would be harder in that one would need to collect the info
> for cpu model and gcc version or maybe 'gentoo/portage version' too.
>
> Id comment that once we had the data, creating a script on the install
> disk wouldnt be hard, but Im sure that would take away a little more
> of the 'hacker' spirit of the whole install process :-)
>
>
> cheers,
> cam
>
> --
> / `Rev Dr' cam at darkqueen.org Roleplaying, virtual goth \
> < http://darkqueen.org Poly, *nix, Python, C/C++, genetics, ATM >
> \ [+61 3] 9809 1523[h] skeptic, Evil GM(tm). Sysadmin for hire /
> ---------- Random Quote ----------
> Don't kiss an elephant on the lips today.
>
> --
> gentoo-ppc-user@gentoo.org mailing list

--
*******************************************
Dr. Erik Zeek
Postdoctoral Research Associate
Department of Physics and Astronomy
The University of Georgia
Athens, GA 30602-2451

Tel: 706-542-7293
Email: mailto:zeekec@mad.scientist.com
Html: http://www.physast.uga.edu/~zeekec
*******************************************
Against stupidity the very gods
Themselves contend in vain.
- Johann Christoph Friedrich von Schiller (1801)
*******************************************

On Mon, Feb 21, 2005 at 08:10:17AM -0600, Christopher Hota wrote:
> On my new 12" Aluminum PowerBook, I'm using the following with no
> problems (results in spankin-fast binaries, too):
>
> CFLAGS="-O2 -pipe -mcpu=7450 -maltivec -mabi=altivec -mpowerpc-gfxopt
> -fsigned-char -mstring -mmultiple"
> CHOST="powerpc-unknown-linux-gnu"
> CXXFLAGS="${CFLAGS}"
> MAKEOPTS="-j3"
>

Hi,

I'm just wondering if the -mmultiple people actually test if -mmultiple
increases performance on their CPU... because this enables the use of
load multiple word from my understanding and this instruction might be
quite expensive depending on the CPU implementation.

-fsigned-char is the not the default?



David

---

David Bélanger
Web page: http://www.cs.mcgill.ca/~dbelan2/
Public key: http://www.cs.mcgill.ca/~dbelan2/public_key.txt


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