10 May
2004
10 May
'04
2:25 p.m.
Good question. I had already read that and was curious myself. Also, how about
2.6.6-mm1? I want to upgrade to Fedora Core 2 and a new kernel so I can quit
pissing off Paul D. and the guys with my 2.96 gcc ;-)
Jan
On Mon, 10 May 2004 16:50 , Robert Jonsson <robert.jonsson(a)dataductus.se> sent:
Hi,
As a service to all readers, here's an excerpt of the Changelog concerning
latency: ;)
akpm(a)osdl.org>
[PATCH] Add mpage_writepages() scheduling point
From: Jens Axboe axboe(a)suse.de>
Takashi did some nice latency testing of the current kernel (with -mm
writeback changes), and the biggest offender in general core is
mpage_writepages().
akpm(a)osdl.org>
[PATCH] ia32: 4Kb stacks (and irqstacks) patch
From: Arjan van de Ven arjanv(a)redhat.com>
Below is a patch to enable 4Kb stacks for x86. The goal of this is to
1) Reduce footprint per thread so that systems can run many more threads
(for the java people)
2) Reduce the pressure on the VM for order > 0 allocations. We see real life
workloads (granted with 2.4 but the fundamental fragmentation issue isn't
solved in 2.6 and isn't solvable in theory) where this can be a problem.
In addition order > 0 allocations can make the VM "stutter" and give
more
latency due to having to do much much more work trying to defragment
akpm(a)osdl.org>
[PATCH] reiserfs: scheduling latency improvements
akpm(a)osdl.org>
[PATCH] unmap_vmas latency improvement
unmap_vmas() will cause scheduling latency when tearing down really big vmas
on !CONFIG_PREEMPT. That's a bit unkind to the non-preempt case, so let's do
a cond_resched() after zapping 1024 pages.
So... humbly asking, is it time yet to make the switch? :-)
12 May
12 May
6:30 a.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
On mån, 2004-05-10 at 18:05, eviltwin69(a)cableone.net wrote:
Good question. I had already read that and was
curious myself. Also, how about
2.6.6-mm1? I want to upgrade to Fedora Core 2 and a new kernel so I can quit
pissing off Paul D. and the guys with my 2.96 gcc ;-)
On a related question: I went to town today and saw that for ~15 euro I
can get a magazine with either Mandrake 10 (Community) or SuSE (Tech
Review) as a bonus CD.
Both are kernel 2.6.x with ALSA "out of the box" (I believe?), but which
one should I choose?
/jens
Jan
6:50 a.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
On Wednesday 12 May 2004 10.25, Jens M Andreasen wrote:
On mån, 2004-05-10 at 18:05, eviltwin69(a)cableone.net
wrote:
Okay, the fight is on! ;-)
Being a long time user of Mandrake only, I can not vouch for the usability of
Suse. I am however using Mandrake 10 in multiple installations right now so I
thought I would comment.
A point list of bad things:
- For audio work the bundled 2.6 kernel is not good enough.
- I also had problems with the the one that thac released (rpm.nyvalls.se)
so I downgraded to kernel-multimedia-2.4.22.21mm.2mdk-1-1mdk, which works
just fine. Now I see that thac has released new 2.6 kernels which maybe
are better... I will try on a rainy day.
- 10 is supposed to have very good usb support, which was not quite what I
have experienced. It appears to be kernel problems though, when I downgraded
the kernel my usb stuff started to work (keyboard and mouse, before you ask,
YES I had a standard PS2 keyboard connected, my brainwaves was not strong
enough to control it, though I tried.)
The good things (more generic):
- Mandrake tends (in my opinion) to favour freshness above stability.
in my book this is only for the good, no stale packages, everything is
up to date.
- New packages appear swiftly and are freely available at a number of
repositories, this is a real boon.
- The config tools get better and better for each release, I don't recall
having any problems with them in the current release (oh maybe with the
printer now that I come to think of it)
That is all, awaiting counter attack. ;)
/Robert
Good question. I had already read that and was
curious myself. Also,
how about 2.6.6-mm1? I want to upgrade to Fedora Core 2 and a new kernel
so I can quit pissing off Paul D. and the guys with my 2.96 gcc ;-)
On a related question: I went to town today and saw that for ~15 euro I
can get a magazine with either Mandrake 10 (Community) or SuSE (Tech
Review) as a bonus CD.
Both are kernel 2.6.x with ALSA "out of the box" (I believe?), but which
one should I choose? 
7:12 a.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
Hallo,
Robert Jonsson hat gesagt: // Robert Jonsson wrote:
A point list of bad things:
- For audio work the bundled 2.6 kernel is not good enough.
This depends on the kind of audio work you do. I can do all I want
reliably with 2.6 since I installed 2.6.3 the first time. I don't
record 12 channel audio, though. But it's oversimplifying to say, that
2.6 isn't good enough "for audio work". It's very good and almost
perfect for many kinds of audio work.
Ciao
--
Frank Barknecht _ ______footils.org__
9:10 a.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
On ons, 2004-05-12 at 11:04, Frank Barknecht wrote:
Hallo,
Robert Jonsson hat gesagt: // Robert Jonsson wrote:
To clearify: I use my linuxbox almost exclusively as a realtime
midi-synthesizer. The occasional "hick-up" is not a problem, or at least
it is no worse than the audience stepping with high heels and
vacuumcleaners into my patchwork ...
I have Mandrake 9.2 installed now, and except for the upgrade to GTK2 it
is mostly a downgrade (from Mandrake 8.2.)
If I am to downgrade even further and wipe a working system, I would
like the following to runable:
1) A working gcc/emacs combination.
2) A working mail/usenet/www combination.
3) A working TeX/LaTeX/LyX combination (Not required.)
Mmmm ...
4) This machine works both as a firewall and a shared conection without
me knowing so very much about how to do. The "audience" would like to
keep it that way.
Can I get all of this? And have a realtime working ALSA too?
To reiterate the question: SuSE 9.0 or Mandrake 10.0?
/jens
A point list of bad things:
- For audio work the bundled 2.6 kernel is not good enough.
This depends on the kind of audio work you do. I can do all I want
reliably with 2.6 since I installed 2.6.3 the first time. I don't
record 12 channel audio, though. But it's oversimplifying to say, that
2.6 isn't good enough "for audio work". It's very good and almost
perfect for many kinds of audio work.
Ciao
11:11 a.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
Hallo,
Jens M Andreasen hat gesagt: // Jens M Andreasen wrote:
To clearify: I use my linuxbox almost exclusively as a
realtime
midi-synthesizer. The occasional "hick-up" is not a problem, or at least
it is no worse than the audience stepping with high heels and
vacuumcleaners into my patchwork ...
Well, to clarify as well: 2.6 isn't as "good" as a well patched 2.4
but it's much easier to set up. If using the realtime-lsm module you
don't even need to recompile a distribution's 2.6 kernel in many
cases, whereas this is often necessary with standard 2.4 kernels.
So I'd suggest to try 2.6.6 at first, then if you encounter problems,
you might want to go 2.4 patched for low latency and maybe
preepmtible.
Can I get all of this? And have a realtime working
ALSA too?
Should be no problem: My machine also is a general purpose machine in
the daylight and converts to a sound box at night. ;)
To reiterate the question: SuSE 9.0 or Mandrake 10.0?
This I cannot comment. I use Debian and I don't want to switch,
because it's the best distribution of all. As is Suse, Mandrake,
Gentoo, Fedora, Slack, ...
Generally spoken: It doesn't matter at all which distribution you
choose, as long as you're comfortable with the package management and
administration tools of your distribution. Learn that, and you will be
able to set up a well working audio box with every distribution.
Ciao
--
Frank Barknecht _ ______footils.org__
11:30 a.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
On Wed, May 12, 2004 at 03:03:27PM +0200, Frank Barknecht wrote:
Jens M Andreasen hat gesagt: // Jens M Andreasen
wrote:
> To reiterate the question: SuSE 9.0 or Mandrake
10.0?
I've been using a standard SuSE 9.0 (2.4) for about six months now,
and it performs very well for audio work. SuSE kernels normally
have (most of) the low-latency and pre-emption patches built-in
from the start. I don't know what SuSE did with the experimental
2.6 in 9.0 or the official 2.6 in 9.1.
--
FA
11:51 a.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
On Wednesday 12 May 2004 14:22, Alfons Adriaensen wrote:
I've been using a standard SuSE 9.0 (2.4) for
about six months now,
and it performs very well for audio work.
Are you using the stock 2.4.21 kernel? Any idea how to enable capabilities on it?
I've been playing around with SuSE 9.0 over the last couple of days and with an
SBLive am only get reasonably xrun-free performance with jackd at 2048, 2 periods.
I'd like to enable caps and use jackstart to see if that makes a difference but after
a couple of days of prodding about only found one oblique reference to modifying
CAP_INIT_EFF_SET and CAP_INIT_INH_SET in include/linux/capability.h. Even then the
kernel
I ended up building wouldn't boot - my usual standard of kernel build I hasten to
add..
Any clues?
R
12:10 p.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
Richard Bown <richard.bown(a)ferventsoftware.com> writes:
Are you using the stock 2.4.21 kernel? Any idea how
to enable
capabilities on it? I've been playing around with SuSE 9.0 over the
last couple of days and with an SBLive am only get reasonably
xrun-free performance with jackd at 2048, 2 periods. I'd like to
enable caps and use jackstart to see if that makes a difference but
after a couple of days of prodding about only found one oblique
reference to modifying CAP_INIT_EFF_SET and CAP_INIT_INH_SET in
include/linux/capability.h. Even then the kernel I ended up building
wouldn't boot - my usual standard of kernel build I hasten to add..
That sounds like the right patch. It's just two lines.
Then, you have to build a working kernel. There are lots of HOWTOs
and other documents on that. Often it's good to start with a working
.config from your distribution. Unfortunately, those usually depend
on an initrd for crucial device drivers these days. Patiently
checking all those options is probably the best approach. Make sure
the boot device driver and file system are included in the kernel, not
built as modules, etc.
Any clues?
The JACK FAQ has reasonably complete instructions for the capabilities
patch.
http://jackit.sourceforge.net/docs/faq.php#a5
Sounds like you already did that.
--
joq
1:23 p.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
On Wednesday 12 May 2004 15:02, Jack O'Quin wrote:
Then, you have to build a working kernel.
Alfons gave me the inside line on that off-list:
"On SuSE, you need to do a 'make cloneconfig' before the 'make
menuconfig'
and all the rest. This is easily forgotten, usually giving you a kernel
that doesn't work."
Something I didn't know. However it didn't do the trick quite yet as the
resulting
kernel was still borked. I'll try a "make distclean" and start again.
I take the point about capabilities being of no use if you can't run jackd with
realtime anyway. I just guessed that capabilities might allow me to run jackd
with realtime in the first place - I think the main problem I'got is that the card
won't run duplex at a decent, small period size full stop i.e. ALSA can't set
period
size to 256 frames for capture. I don't think capabilities, root or whatever will
fix that.
So perhaps I'll just think about getting myself a decent soundcard. Well I've
got
that SW1000XG of course but that's opening up a whole other kettle of fish..
R
7:17 p.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
Richard Bown wrote:
"On SuSE, you need to do a 'make
cloneconfig' before the 'make menuconfig'
and all the rest. This is easily forgotten, usually giving you a kernel
that doesn't work."
Something I didn't know. However it didn't do the trick quite yet as the
resulting
kernel was still borked. I'll try a "make distclean" and start again.
That sounds like you're sources are still misconfigured. I had this
effect on an AMD system as well, and only with SuSE 9.0. The symptom was
some unresolved symbols when trying to load the reiserfs module,
resulting in a kernel panic at boot time because the root fs could not
be mounted. Try a "make mrproper" in /usr/src/linux and go through the
entire configure/build process again. You should be able to get more
info by scribbling down the kernel panic message and googling for it.
Good luck!
I take the point about capabilities being of no use if
you can't run jackd with
realtime anyway. I just guessed that capabilities might allow me to run jackd
with realtime in the first place
The cap patch lets you run jackd (using the jackstart wrapper program)
with realtime priorities without having to run it as root. If jack does
run as root (using sudo, setsuid or whatever) you get the same effect
without having to patch the kernel.
On my SuSE 9.0 system, this makes a *great* difference. I still have
some gripes using SuperCollider with Jack, when the system is under high
load, but all in all Jack runs very smooth at low latencies.
Albert
--
Dr. Albert Gr"af
Dept. of Music-Informatics, University of Mainz, Germany
Email: Dr.Graef(a)t-online.de, ag(a)muwiinfa.geschichte.uni-mainz.de
WWW: http://www.musikwissenschaft.uni-mainz.de/~ag
13 May
13 May
4:58 a.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
On Wednesday 12 May 2004 21:54, Albert Graef wrote:
[SuSE 9.0 and capabilities]
That sounds like you're sources are still
misconfigured.
I was just being a doofus. I hadn't "made clean" after "make
dep".
So the simple steps to getting it working were: make cloneconfig;
make dep; make clean; make bzImage. The problem I had was the bzImage
looked pretty much the same physical size whether I'd "make clean"
or not.
Try a "make mrproper"
What does that do?
[the patch]
On my SuSE 9.0 system, this makes a *great*
difference.
Yes, I can attest to that too now. Many thanks for the various
tips - the lowest period size I can obtain now with jackstart and
--realtime in duplex with the SBLive is now 512 (which is OK) and
it's pretty stable there.
R
5:08 a.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
Hi,
<...>
512 is the smallest buffer size the emu10k1 driver will allow in duplex mode.
The hardware can infact go much lower. I have no idea where this limitation
is originating (well yes, it's in alsa, but I don't know how come).
/Robert
On my SuSE 9.0
system, this makes a *great* difference.
Yes, I can attest to that too now. Many thanks for the various
tips - the lowest period size I can obtain now with jackstart and
--realtime in duplex with the SBLive is now 512 (which is OK) and
it's pretty stable there.
R
4 p.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
Richard Bown wrote:
"The command "make mrproper" insures that you have a pristine source
tree." (whatever that means ...)
See http://www.google.com/search?q=make+mrproper :)
--
Dr. Albert Gr"af
Dept. of Music-Informatics, University of Mainz, Germany
Email: Dr.Graef(a)t-online.de, ag(a)muwiinfa.geschichte.uni-mainz.de
WWW: http://www.musikwissenschaft.uni-mainz.de/~ag
Try a
"make mrproper"
What does that do?
12 May
12 May
12:24 p.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
Hallo,
Richard Bown hat gesagt: // Richard Bown wrote:
On Wednesday 12 May 2004 14:22, Alfons Adriaensen
wrote:
This sounds like a problem building kernels which can have many
reasons. Still, you can check if you're able to get better results by
running plain jackd as root with --realtime set. If this won't make
things better, then the capabilities stuff will help you nothing, as
those just make it easier to run applications with higher scheduling
than having to run them as root. But cap won't help getting lower
latencies at all.
If running as root doesn't help, then you need to either patch your
kernel the old fashioned way with low latency etc. Or try stock 2.6.6.
For this you can also build a realtime module that won't need the
cap-patch anymore.
Ciao
--
Frank Barknecht _ ______footils.org__
I've been using a standard SuSE 9.0 (2.4) for
about six months
now, and it performs very well for audio work.
Are you using the stock 2.4.21 kernel? Any idea how to enable
capabilities on it? I've been playing around with SuSE 9.0 over the
last couple of days and with an SBLive am only get reasonably
xrun-free performance with jackd at 2048, 2 periods. I'd like to
enable caps and use jackstart to see if that makes a difference but
after a couple of days of prodding about only found one oblique
reference to modifying CAP_INIT_EFF_SET and CAP_INIT_INH_SET in
include/linux/capability.h. Even then the kernel I ended up
building wouldn't boot - my usual standard of kernel build I hasten
to add.. 
5:10 p.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
On Wed, May 12, 2004 at 03:03:27PM +0200, Frank
Barknecht wrote:
I'd suggest checking out Gentoo. It takes longer to get your head around at
first, but after that, experimenting with different kernels is really easy.
And the gentoo packages work soooo well. Installing alsa and jack was as
simple as typing "emerge alsa" etc. Ditto for the kernels because you can
download kernel source packages for various kinds of customization including
specifically for multi-media with the low latency and pre-emp patches
applied already.
Iain
Jens M Andreasen hat gesagt: // Jens M Andreasen
wrote:
> To reiterate the question: SuSE 9.0 or
Mandrake 10.0?
I've been using a standard SuSE 9.0 (2.4) for about six months now,
and it performs very well for audio work. SuSE kernels normally
have (most of) the low-latency and pre-emption patches built-in
from the start. I don't know what SuSE did with the experimental
2.6 in 9.0 or the official 2.6 in 9.1. 
10:43 p.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
iain duncan wrote:
I have to second the gentoo vote. I searched distributions for a while
for something that would meet the audio demands and gentoo really
has met the need the best. Don't get me wrong, there is a steep
learning curve, but it has been well worth it.
Larry Lines
On Wed, May 12,
2004 at 03:03:27PM +0200, Frank Barknecht wrote:
I'd suggest checking out Gentoo. It takes longer to get your head around at
first, but after that, experimenting with different kernels is really easy.
And the gentoo packages work soooo well. Installing alsa and jack was as
simple as typing "emerge alsa" etc. Ditto for the kernels because you can
download kernel source packages for various kinds of customization including
specifically for multi-media with the low latency and pre-emp patches
applied already.
Iain
Jens M Andreasen hat gesagt: // Jens M Andreasen
wrote:
>To reiterate the question: SuSE 9.0 or Mandrake 10.0?
>
>
I've been using a standard SuSE 9.0 (2.4) for about six months now,
and it performs very well for audio work. SuSE kernels normally
have (most of) the low-latency and pre-emption patches built-in
from the start. I don't know what SuSE did with the experimental
2.6 in 9.0 or the official 2.6 in 9.1.
13 May
13 May
10:46 a.m.
New subject: [linux-audio-dev] kernel 2.6.6 just out
At Wed, 12 May 2004 15:22:06 +0200,
Alfons Adriaensen wrote:
On Wed, May 12, 2004 at 03:03:27PM +0200, Frank Barknecht wrote:
no, preemption patch is not included.
Jens M Andreasen hat gesagt: // Jens M Andreasen
wrote:
> To reiterate the question: SuSE 9.0 or
Mandrake 10.0?
I've been using a standard SuSE 9.0 (2.4) for about six months now,
and it performs very well for audio work. SuSE kernels normally
have (most of) the low-latency and pre-emption patches built-in
from the start. I don't know what SuSE did with the experimental
2.6 in 9.0 or the official 2.6 in 9.1.
some additional lowlatency patches are in SUSE 9.1 kernel.
most of them have been already included in mm tree.
again, no preemption in 9.1 kernel.
SUSE's policy is to ship the same kernel for all ranges, i.e. from
consumer to server. preemption may bring too much overhead for the
highend use.
(in the case of 2.6 kernels, one can rebuild easily own kernel with
preemption, though.)
in my test cases, reiserfs is working well on my machine.
there are still some latency causes. in addition to driver-specific
problems (e.g. sis900 results in 3ms peaks in the timer interrupt
context), VM/FS-related things like RCU handling in tasklet, dcache
shrinking, etc. may result in some high latencies. but it won't
happen unless you create/remove thousands of files at once.
perhaps the bigger problem is the latency in drm modules, as Fernando
reported. (i disable DRM on my machine, so didn't notice it.)
Takashi
7290
days inactive
7293
days old
linux-audio-dev@lists.linuxaudio.org
17 comments
11 participants
participants (11)
-
Alfons Adriaensen -
Dr.Graef＠t-online.de -
eviltwin69＠cableone.net -
Frank Barknecht -
iain duncan -
Jack O'Quin -
Jens M Andreasen -
Larry Lines -
Richard Bown -
Robert Jonsson -
Takashi Iwai