Re: Bug#652469: Bug#652448: panic when booting on a machine with = 4 GiB of RAM

2011-12-17 Thread Arno Töll
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1

On 17.12.2011 15:49, Robert Millan wrote:
 I'm not sure how relevant is
 this factor but it is unexistant on GNU/kFreeBSD, so I think this
 should be accounted for when taking Linux as reference.

More or less unexisting. The very same candidates that would cause one
to remain on a IA32 user land because of non-free cruft on Linux mostly
also holds FreeBSD as it is typically the very same software people want
to run through the Linux emulation layer. Think of Flash and Google
Earth for example. That said I have no use for kfreebsd on a desktop and
I hence didn't try any of those programs under kfreebsd so far.

 Another likely difference is that kFreeBSD in PAE mode has major
 drawbacks (in particular we'd have to disable a bunch of drivers, see
 sys/i386/conf/PAE and URL I pasted before). All in all, I have the
 impression that using PAE would be unacceptable for the majority of
 i686 users.

That on the other hand is a good rationale not to use PAE. However, if
you read the discussion I noted there is no significant performance
improvement [on Linux] to use i686 over i486. Thus, users of 686 capable
CPUs may happily use the 486 branch, whereas people who need PAE need
686 anyway.

 Good question.  TBH I really dislike adding new flavours for PAE
 unless SMP is merged.  Then we'd only have to replace 686-smp with
 686-pae instead of adding two new flavours.

We're not freezing tomorrow, maybe consider waiting for upstream
regarding SMP support upstream.

 I don't know if SMP option is really usable on uniprocessor hardware.
 FWIW, I've tested -smp flavours for 8.3 and 9.0 on an uniprocessor VM
 and both seem to work fine.

I would hope it is usable. If it weren't that would certainly be a bug
in the SMP code. However, there might be design decisions that make SMP
slower on uniprocessor hardware (or not - I don't know as said).

 Maybe we should discuss this with FreeBSD? We could even propose them
 to make SMP the default there.

That makes sense, yes. In particular I guess we shouldn't be inventing
use cases which aren't supported in such a configuration upstream either.

 Given that a PAE kernel has important drawbacks (like disabling a lot
 of drivers), I'd rather leave it to the user to explicitly install
 those kernels after a normal kFreeBSD is running.

I wrote that under the impression that such a kernel would crash on
systems with more than 4G RAM. That would leave people without
possibility to install kfreebsd. If that's sorted out, i.e. the bug has
been fixed I am for a non PAE kernel too. I do not think there would be
any benefit to use = 4G RAM in the context of D-I.



- -- 
with kind regards,
Arno Töll
IRC: daemonkeeper on Freenode/OFTC
GnuPG Key-ID: 0x9D80F36D
-BEGIN PGP SIGNATURE-
Version: GnuPG v1.4.11 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/
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=2Cdd
-END PGP SIGNATURE-


-- 
To UNSUBSCRIBE, email to debian-bsd-requ...@lists.debian.org
with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Archive: http://lists.debian.org/4eecb0ac.1060...@toell.net



Bug#652469: Fwd: Re: Bug#652469: Bug#652448: panic when booting on a machine with = 4 GiB of RAM

2011-12-17 Thread Arno Töll
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1

Forward to  652...@bugs.debian.org I forgot, sorry.

-  Original Message 

On 17.12.2011 15:49, Robert Millan wrote:
 I'm not sure how relevant is
 this factor but it is unexistant on GNU/kFreeBSD, so I think this
 should be accounted for when taking Linux as reference.

More or less unexisting. The very same candidates that would cause one
to remain on a IA32 user land because of non-free cruft on Linux mostly
also holds FreeBSD as it is typically the very same software people want
to run through the Linux emulation layer. Think of Flash and Google
Earth for example. That said I have no use for kfreebsd on a desktop and
I hence didn't try any of those programs under kfreebsd so far.

 Another likely difference is that kFreeBSD in PAE mode has major
 drawbacks (in particular we'd have to disable a bunch of drivers, see
 sys/i386/conf/PAE and URL I pasted before). All in all, I have the
 impression that using PAE would be unacceptable for the majority of
 i686 users.

That on the other hand is a good rationale not to use PAE. However, if
you read the discussion I noted there is no significant performance
improvement [on Linux] to use i686 over i486. Thus, users of 686 capable
CPUs may happily use the 486 branch, whereas people who need PAE need
686 anyway.

 Good question.  TBH I really dislike adding new flavours for PAE
 unless SMP is merged.  Then we'd only have to replace 686-smp with
 686-pae instead of adding two new flavours.

We're not freezing tomorrow, maybe consider waiting for upstream
regarding SMP support upstream.

 I don't know if SMP option is really usable on uniprocessor hardware.
 FWIW, I've tested -smp flavours for 8.3 and 9.0 on an uniprocessor VM
 and both seem to work fine.

I would hope it is usable. If it weren't that would certainly be a bug
in the SMP code. However, there might be design decisions that make SMP
slower on uniprocessor hardware (or not - I don't know as said).

 Maybe we should discuss this with FreeBSD? We could even propose them
 to make SMP the default there.

That makes sense, yes. In particular I guess we shouldn't be inventing
use cases which aren't supported in such a configuration upstream either.

 Given that a PAE kernel has important drawbacks (like disabling a lot
 of drivers), I'd rather leave it to the user to explicitly install
 those kernels after a normal kFreeBSD is running.

I wrote that under the impression that such a kernel would crash on
systems with more than 4G RAM. That would leave people without
possibility to install kfreebsd. If that's sorted out, i.e. the bug has
been fixed I am for a non PAE kernel too. I do not think there would be
any benefit to use = 4G RAM in the context of D-I.



-BEGIN PGP SIGNATURE-
Version: GnuPG v1.4.11 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/
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=E/Ed
-END PGP SIGNATURE-



-- 
To UNSUBSCRIBE, email to debian-bsd-requ...@lists.debian.org
with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Archive: http://lists.debian.org/4eecb15b.7070...@toell.net



Bug#652469: Fwd: Re: Bug#652469: Bug#652448: panic when booting on a machine with = 4 GiB of RAM

2011-12-17 Thread Edward Tomasz Napierała
Wiadomość napisana przez Arno Töll w dniu 17 gru 2011, o godz. 16:12:
 Maybe we should discuss this with FreeBSD? We could even propose them
 to make SMP the default there.

SMP has been enabled in the the default FreeBSD kernel (GENERIC)
for quite some time now.

-- 
If you cut off my head, what would I say?  Me and my head, or me and my body?




--
To UNSUBSCRIBE, email to debian-bsd-requ...@lists.debian.org
with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Archive: 
http://lists.debian.org/84d9a0cf-6981-4244-a881-566cb2a11...@freebsd.org