You are not logged in.

#1 2009-10-20 00:31:16

Vamp898
Member
From: ドイツではまだ住んでいる
Registered: 2009-01-03
Posts: 866
Website

Arch kernel with PAE

I asked some times ago about including PAE (HIGHMEM) in the offical Arch Kernel in x86 and i was said no beceause it is slower and when i want more than 4gb memory i should use x86_64

now i seen. 32bit is not slower with PAE. Only the stuff over 3GB is slower than with 64bit.

So the argoument PAE is slower is nonsense beceause the memory which is accessed slower is not existing without PAE so we have the choose between

No Memory over 3GB
Slow Memory over 3GB or lemme say not fast as it can be

the first 3GB are the same speed with and without PAE so maybe we should re-think about this

Last edited by Vamp898 (2009-10-20 00:32:29)

Offline

#2 2009-10-20 00:44:09

Allan
Member
From: Brisbane, AU
Registered: 2007-06-09
Posts: 10,867
Website

Re: Arch kernel with PAE

That seems a well formed opinion with lots of evidence to back it up....   i.e. links to the place where you got this information would be good.

Offline

#3 2009-10-20 00:47:28

Vamp898
Member
From: ドイツではまだ住んでいる
Registered: 2009-01-03
Posts: 866
Website

Re: Arch kernel with PAE

You can simple benchmark it yourself^^ i just installed kernel26-pae before i switched to x86_64. i switched to 64bit beceause it takes to much time for me to compile the whole kernel with all unneede drivers (for me).

Just write a simple bashscript or maybe want to use a complex benchmark that pump up your memory.

on 32bit with/without PAE the first 3GB will be the exactly same speed.
on 32bit with pae the memory fills up to 4gb but getting much slower after ~3,3GB on 64bit it keeps the full speed.

64bit brings to much problems so i want to switch back to 32bit^^ so i would be lucky about having full 4GB without hours of compiling

Last edited by Vamp898 (2009-10-20 00:48:41)

Offline

#4 2009-10-20 00:51:27

flamelab
Member
From: Athens, Hellas (Greece)
Registered: 2007-12-26
Posts: 2,160

Re: Arch kernel with PAE

What problems do you have on x64 ? I'm using Arch x64 since 2007 and the only one (1) problem is Flash.

Offline

#5 2009-10-20 00:52:44

Vamp898
Member
From: ドイツではまだ住んでいる
Registered: 2009-01-03
Posts: 866
Website

Re: Arch kernel with PAE

http://bbs.archlinux.org/viewtopic.php?id=82737

my printer does not work (drivers are only aviable for 32bit)

higher memory usage and so on

Offline

#6 2009-10-20 00:52:50

ngoonee
Forum Fellow
From: Between Thailand and Singapore
Registered: 2009-03-17
Posts: 7,231

Re: Arch kernel with PAE

Why not just compile the kernel once and hold the version unless you really need to upgrade?

All I see you saying in this thread is:-
1. I'm having problems
2. I think there's no speed difference using PAE, according to my tests on my machine
3. I want Arch kernel (which everyone else also uses) to be compiled with PAE

If you could prove 2 (and not ask the devs to spend their time, which is OBVIOUSLY less valuable than yours) objectively, then 3 may be a go. If not, then instead of the devs spending a hundred man-hours doing testing, why not you spend 1 hour compiling your own kernel.


Allan-Volunteer on the (topic being discussed) mailn lists. You never get the people who matters attention on the forums.
jasonwryan-Installing Arch is a measure of your literacy. Maintaining Arch is a measure of your diligence. Contributing to Arch is a measure of your competence.
Griemak-Bleeding edge, not bleeding flat. Edge denotes falls will occur from time to time. Bring your own parachute.

Offline

#7 2009-10-20 00:54:52

Vamp898
Member
From: ドイツではまだ住んでいる
Registered: 2009-01-03
Posts: 866
Website

Re: Arch kernel with PAE

i know a lot people which have 4gb and using 32bit in case of stuff which not works on 64bit for them

i would proof it myself but im using 64bit right now and reinstall with 32bit, compiling PAE kernel and maybe reinstall 64bit until this is clear takes much more time than 1 hour

Last edited by Vamp898 (2009-10-20 00:56:07)

Offline

#8 2009-10-20 01:00:31

ngoonee
Forum Fellow
From: Between Thailand and Singapore
Registered: 2009-03-17
Posts: 7,231

Re: Arch kernel with PAE

If you can't spend the time, don't ask others to spend it for you.

And "I know a lot of people" doesn't cut it. Leave aside the fact that its unprovable, it still depends on the dev's decisions. And its not helpful to assume your time is more valuable than thiers in this case (especially since the 32-bit PAE kernel is in the AUR, or easily self-compiled from ABS).


Allan-Volunteer on the (topic being discussed) mailn lists. You never get the people who matters attention on the forums.
jasonwryan-Installing Arch is a measure of your literacy. Maintaining Arch is a measure of your diligence. Contributing to Arch is a measure of your competence.
Griemak-Bleeding edge, not bleeding flat. Edge denotes falls will occur from time to time. Bring your own parachute.

Offline

#9 2009-10-20 01:08:33

Vamp898
Member
From: ドイツではまだ住んでいる
Registered: 2009-01-03
Posts: 866
Website

Re: Arch kernel with PAE

the last time i used kernel26-pae, DRM for my intel card did not worked so its not this easy at all.

This Page http://linux-mm.org/HighMemory maybe helps

Last edited by Vamp898 (2009-10-20 01:50:57)

Offline

#10 2009-10-20 01:23:29

flamelab
Member
From: Athens, Hellas (Greece)
Registered: 2007-12-26
Posts: 2,160

Re: Arch kernel with PAE

Vamp898 wrote:

http://bbs.archlinux.org/viewtopic.php?id=82737

my printer does not work (drivers are only aviable for 32bit)

higher memory usage and so on

I see no problem.

If you have 4 GB of RAM, a slightly ( I mean slightly) higher memory usage isn't a problem. When I login into KDE4, with many daemons running in background + preload, I have 450 MB of usage. Is that so much ?

Offline

#11 2009-10-20 01:34:54

Vamp898
Member
From: ドイツではまだ住んでいる
Registered: 2009-01-03
Posts: 866
Website

Re: Arch kernel with PAE

flamelab wrote:
Vamp898 wrote:

http://bbs.archlinux.org/viewtopic.php?id=82737

my printer does not work (drivers are only aviable for 32bit)

higher memory usage and so on

I see no problem.

If you have 4 GB of RAM, a slightly ( I mean slightly) higher memory usage isn't a problem. When I login into KDE4, with many daemons running in background + preload, I have 450 MB of usage. Is that so much ?

im doing a lot with virtual machines and virtual machines are thankfully for every MB they get. Especially when you run more than one

and KDE4 is only fresh after login on 450mb. When you start using it as a normal person it never gets under 600mb

Offline

#12 2009-10-20 02:04:45

Vamp898
Member
From: ドイツではまだ住んでいる
Registered: 2009-01-03
Posts: 866
Website

Re: Arch kernel with PAE

Vamp898 wrote:

the last time i used kernel26-pae, DRM for my intel card did not worked so its not this easy at all.

This Page http://linux-mm.org/HighMemory maybe helps

When this page is not enough for you. i asked some guys in ##linux and #gentoo and they told me there is only a speed difference when you have more than 4GB. The same like i tested myself. As long you just needs 3GB of your memory there is no difference between non-pae/pae. Only the stuff over 4gb is effected

Last edited by Vamp898 (2009-10-20 02:07:41)

Offline

#13 2009-10-20 02:15:00

Allan
Member
From: Brisbane, AU
Registered: 2007-06-09
Posts: 10,867
Website

Re: Arch kernel with PAE

That is very strange (and dare I say wrong) given how PAE works...   it is not as if it uses it memory mapping only when needing greater than 3Gb of memory, it needs to use it all the time:  http://en.wikipedia.org/wiki/Physical_Address_Extension

And here is the only real attempt at benchmarks I have seen.  Although it is a bit old...

http://people.redhat.com/nmurray/RHEL-2.1-VM-whitepaper.pdf wrote:

The performance impact is highly workload dependent, but on a fairly typical kernel
compile, the PAE penalty works out to be around a 1% performance hit on Red
Hat's test boxes. Testing with various other workload mixes has given performance
hits ranging from 0% to 10%.

Offline

#14 2009-10-20 02:19:35

Vamp898
Member
From: ドイツではまだ住んでいる
Registered: 2009-01-03
Posts: 866
Website

Re: Arch kernel with PAE

Allan wrote:

That is very strange (and dare I say wrong) given how PAE works...   it is not as if it uses it memory mapping only when needing greater than 3Gb of memory, it needs to use it all the time:  http://en.wikipedia.org/wiki/Physical_Address_Extension

And here is the only real attempt at benchmarks I have seen.  Although it is a bit old...

http://people.redhat.com/nmurray/RHEL-2.1-VM-whitepaper.pdf wrote:

The performance impact is highly workload dependent, but on a fairly typical kernel
compile, the PAE penalty works out to be around a 1% performance hit on Red
Hat's test boxes. Testing with various other workload mixes has given performance
hits ranging from 0% to 10%.

wow its really a bit old hmm and i dont know how it was tested hmm

is there a really good way to benchmark it?

i just written a bash skript which pumped up the memory and taked the time until it needed to reach 3,8GB

Last edited by Vamp898 (2009-10-20 02:30:17)

Offline

#15 2010-01-05 21:33:28

ckristi
Member
From: Bucharest, Romania
Registered: 2006-11-21
Posts: 225

Re: Arch kernel with PAE

I know I mitigated before for the PAE inclusion. Here is some touchable evidence that enabling PAE is not that much of a performance hog:
http://www.phoronix.com/scan.php?page=a … _pae&num=1

At some tests it really is faster than standard 32 bit.. but I don't want to push my luck. And I still want to mention as always: Ubuntu (the most popular Linux distro) and Pardus (a nation-wide spread Linux distribution in Turkey, mostly in schools and public institutions) are already providing an alternative kernel with PAE enabled. Oh, and another mention: Ubuntu Server and Openwall Linux (both being security oriented distros) have PAE enabled by default in their main kernel.

You just HAVE TO see those facts and provide a PAE enabled kernel. It's not hard to do, not at all hard to test and it broke me no configurations (including ATI proprietary modules, NVIDIA proprietary modules.. I also had no problems with Intel graphics drivers at all). I'm offering myself to test this kernel on different machines (and trust me I have a few different hardware configs around that can be used for testing). Needless to say that I'm using PAE kernels for more than 3-4 years in production environments just because there was almost no x86_64 linux distros available at that point in time.


In love I believe and in Linux I trust

Offline

#16 2010-01-05 21:46:41

Allan
Member
From: Brisbane, AU
Registered: 2007-06-09
Posts: 10,867
Website

Re: Arch kernel with PAE

ckristi wrote:

You just HAVE TO see those facts and provide a PAE enabled kernel.

You just HAVE TO see that we provide ABS as a way for people to customize the official packages.

Offline

#17 2010-01-05 22:16:23

ckristi
Member
From: Bucharest, Romania
Registered: 2006-11-21
Posts: 225

Re: Arch kernel with PAE

Well, thanks.. this just made me realise why I should consider not using Arch anymore. Linux is all about choice and you don't want to offer it to your users. Unfortunately my free time is limited (not a student anymore, you know) so I do not have time to play anymore with my home systems to tweak them to my needs. I just need something working in a short period of time. I just don't see any productivity in playing with my .config kernel file on my desktop machines. You do not want to help me and other people who would appreciate this, then ok. You won your free time (for spending it pointing users to do whatever you do not want to do) and I'll win mine... elsewhere. Bye.


In love I believe and in Linux I trust

Offline

#18 2010-01-05 22:27:11

some-guy94
Member
Registered: 2009-08-15
Posts: 360

Re: Arch kernel with PAE

ckristi wrote:

Well, thanks.. this just made me realise why I should consider not using Arch anymore. Linux is all about choice and you don't want to offer it to your users. Unfortunately my free time is limited (not a student anymore, you know) so I do not have time to play anymore with my home systems to tweak them to my needs. I just need something working in a short period of time. I just don't see any productivity in playing with my .config kernel file on my desktop machines. You do not want to help me and other people who would appreciate this, then ok. You won your free time (for spending it pointing users to do whatever you do not want to do) and I'll win mine... elsewhere. Bye.

If you don't have the time to edit the PKGBUILD and add a 'make menuconfig' before the build, how could you have time to help with testing? tongue

Offline

#19 2010-01-05 22:44:27

Misfit138
Misfit Emeritus
From: USA
Registered: 2006-11-27
Posts: 4,172

Re: Arch kernel with PAE

some-guy94 wrote:

If you don't have the time to edit the PKGBUILD and add a 'make menuconfig' before the build, how could you have time to help with testing? tongue

...or time to install, configure and familiarize himself with a new distro? ::shrug::

Offline

#20 2010-01-05 22:46:24

ngoonee
Forum Fellow
From: Between Thailand and Singapore
Registered: 2009-03-17
Posts: 7,231

Re: Arch kernel with PAE

ckristi wrote:

Well, thanks.. this just made me realise why I should consider not using Arch anymore. Linux is all about choice and you don't want to offer it to your users. Unfortunately my free time is limited (not a student anymore, you know) so I do not have time to play anymore with my home systems to tweak them to my needs. I just need something working in a short period of time. I just don't see any productivity in playing with my .config kernel file on my desktop machines. You do not want to help me and other people who would appreciate this, then ok. You won your free time (for spending it pointing users to do whatever you do not want to do) and I'll win mine... elsewhere. Bye.

Seriously, get over yourself. Linux is all about choice, so don't try to force the devs to do something YOU want or tell them they HAVE to do something.

If you don't have the time to do it, don't update your kernel that often. You could even write a quick bash script that includes the appropriate options and run it every time you have an update.

But no, you'd rather someone else did your work.


Allan-Volunteer on the (topic being discussed) mailn lists. You never get the people who matters attention on the forums.
jasonwryan-Installing Arch is a measure of your literacy. Maintaining Arch is a measure of your diligence. Contributing to Arch is a measure of your competence.
Griemak-Bleeding edge, not bleeding flat. Edge denotes falls will occur from time to time. Bring your own parachute.

Offline

#21 2010-01-05 22:56:52

ckristi
Member
From: Bucharest, Romania
Registered: 2006-11-21
Posts: 225

Re: Arch kernel with PAE

I really do not need time to familiarize myself with other distros because, unlike most of the newbies here I'm in the "Linux industry" since Slackware 3.4... so I've seen some distros. And about testing it was my way of saying that I'm willing to contribute. And I contributed to this community without a trace of selfishness each time I felt I can do that. But that's another story that just makes me more frustrated when I try to make some people see that we have the right to demand things without being sent to /dev/null every time we make a request. If you want to be a really competitive distribution, you'd better revise your way of thinking at least a bit. Don't take your users for granted, especially the ones who really tried making this distro better... if you don't believe me check the forum and the bugtracker. And that's the final post on this topic. I'll be back here when I'll feel it's worth it.


In love I believe and in Linux I trust

Offline

#22 2010-01-05 23:40:37

Misfit138
Misfit Emeritus
From: USA
Registered: 2006-11-27
Posts: 4,172

Re: Arch kernel with PAE

All I can do is say I'm sorry you feel the way you do. If you really believe that Arch is on the wrong track and care to discuss it further, I, for one, am willing to accept pm's.
Best of luck, no matter what you decide, but I hope you reconsider leaving.

Offline

Board footer

Powered by FluxBB