Hi, Sloan, Thanks for reply free total used free shared buffers cached Mem: 3631508 995200 2636308 0 99664 592668 -/+ buffers/cache: 302868 3328640 Swap: 915696 0 915696 Are you sure I am need to switch to bigsmp kernel ??? 32-bit standard kernel should recognize 4 GB, or I am wrong ? On Wednesday 20 February 2008 10:39:39 pm Sloan wrote:

Andrei Verovski (aka MacGuru) wrote:

...

Hi !

I have PC box with Core 2 Quad, P35 chipset and 4 GB of RAM (2+2 GB) with 32-bit OpenSuSE 10.3 and kernel-default installed. The most strangest part is that when I open BIOS everything is OK - it shows 4 GB of RAM. However, in Linux with stock "kernel-default" I see only 3.5 GB ! I suppose I do not need to install kernel-bigsmp or switch to 64-bit version of SuSE just to be able to use ALL 4 GB.

Here is a 32-bit suse machine with 4 GB - looks like you may want the bigsmp kernel

root@freeside:~> free total used free shared buffers cached Mem: 4082748 3747028 335720 0 82816 3007352 -/+ buffers/cache: 656860 3425888 Swap: 4198296 8 4198288 root@freeside:~> uname -a Linux freeside 2.6.5-7.267-bigsmp #1 SMP Wed Jun 21 10:50:51 UTC 2006 i686 i686 i386 GNU/Linux root@freeside:~>

Joe

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On Wednesday 20 February 2008 12:57, Andrei Verovski (aka MacGuru) wrote:

Hi, Sloan,

Thanks for reply

free total used free shared buffers cached Mem: 3631508 995200 2636308 0 99664 592668 -/+ buffers/cache: 302868 3328640 Swap: 915696 0 915696

Are you sure I am need to switch to bigsmp kernel ??? 32-bit standard kernel should recognize 4 GB, or I am wrong ?

Joe's right. You have to have a "big" kernel so that the so-called Physical Address Extensions (PAE) are activated and used. Without this, a chunk of the 32-bit physical address space must be set aside for device addresses, and this precludes accessing the full 4 GB of RAM you have installed. Randall Schulz -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org

Alternatively - move to 64-bit OS :) -- -Alexey Eremenko "Technologov" -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The Thursday 2008-02-21 at 02:00 -0800, Tommy Pham wrote:

I second that! Here's the math for the limitation. Since computers operate on binary (0s and 1s) and your particular platform is 32 bit: 2^32 = 4,294,967,296 = 4194304 kb = 4096 mb = 4 gb However on a 64 bit: 2^64 = 18446744073709551616 = 16777216 tb ... you won't be reaching it's limit any time soon :D (reaching the limit is in the engineering of the hardware)

Things are not so simple, because these modern 32 bit processors have in fact 36 address lines, being capable of addressing 64 GiB, not 4. With tricks, of course, like PAE (*), because the registers are 32 bit wide. * http://en.wikipedia.org/wiki/Physical_Address_Extension - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4-svn0 (GNU/Linux) iD8DBQFHvWC7tTMYHG2NR9URApVXAJ4tb/51xE1yK+QNK6mrL2BpCNW+PwCgg6dE HSTATmR+kh9Aghztm7QRCNM= =YKOx -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The Thursday 2008-02-21 at 03:51 -0800, Tommy Pham wrote: (please, trim the quotes)

...

Things are not so simple, because these modern 32 bit processors have in fact 36 address lines, being capable of addressing 64 GiB, not 4. With tricks, of course, like PAE (*), because the registers are 32 bit wide.

* http://en.wikipedia.org/wiki/Physical_Address_Extension

True, you can use (PAE) extensions but inherently being 64 bit is faster since you have more "lanes" to address those memory right?

I haven't said anything to the contrary. Simply that modern 32 bit pentiums can adress 36 address lines, that's the hardware. Similarly, the original x86 had 20 address lines, although the address registers had only 16 bits - due to the use of segment registers. - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4-svn0 (GNU/Linux) iD8DBQFHvXXrtTMYHG2NR9URAkbCAKCOSFb4ac4pqLx8aDz/19o5pdzrkQCeKvY/ pB0P09jgfPWMKWN56J8eioY= =WdzZ -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org

Sloan wrote:

Andrei Verovski (aka MacGuru) wrote:

...

Hi !

I have PC box with Core 2 Quad, P35 chipset and 4 GB of RAM (2+2 GB) with 32-bit OpenSuSE 10.3 and kernel-default installed. The most strangest part is that when I open BIOS everything is OK - it shows 4 GB of RAM. However, in Linux with stock "kernel-default" I see only 3.5 GB ! I suppose I do not need to install kernel-bigsmp or switch to 64-bit version of SuSE just to be able to use ALL 4 GB.

Here is a 32-bit suse machine with 4 GB - looks like you may want the bigsmp kernel

root@freeside:~> free total used free shared buffers cached Mem: 4082748 3747028 335720 0 82816 3007352 -/+ buffers/cache: 656860 3425888 Swap: 4198296 8 4198288 root@freeside:~> uname -a Linux freeside 2.6.5-7.267-bigsmp #1 SMP Wed Jun 21 10:50:51 UTC 2006 i686 i686 i386 GNU/Linux root@freeside:~>

Joe

Here is another 32-bit suse machine with 4 GB and the bigsmp kernel: 08:46 providence~> free -tm total used free shared buffers cached Mem: 3041 2103 938 0 502 1059 -/+ buffers/cache: 541 2500 Swap: 1027 0 1027 Total: 4069 2103 1965 The way it was explained to me is: (from Jeff Mahoney) "Some chipsets don't actually allow access to the full 4 GB. This might be one of them." and (from Philipp Thomas) "Sorry, but it has nothing to do with the physical address space per se. What *does* matter is the PCI bus, more precisely the 32 bit PCI devices. These need addresses below 4 GiB for I/O because that's the limit you can address with 32 bit. PC BIOSes typically reserve 500 MiB or 1GiB for such devices, which results in that many RAM being unavailable (anybody remember the gap between 640 KiB and 1 MiB on the PC that was reserved for BASIC ROM, VIDEO BIOS and the BIOS?). Now some systems offer an option that makes this 'hidden' memory available at addresses *beyond* the 4 GiB threshold. To access this memory you either need a PAE enabled kernel (i.e. a kernel that can handle the diffrent addressing with AFAIR 36 bit) or, on machines supporting x86-64 (aka AMD64/EM64T), a 64 bit kernel." So bottom line, I still have a missing gig. -- David C. Rankin, J.D., P.E. Rankin Law Firm, PLLC 510 Ochiltree Street Nacogdoches, Texas 75961 Telephone: (936) 715-9333 Facsimile: (936) 715-9339 www.rankinlawfirm.com -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org

Joe Sloan wrote:

David C. Rankin wrote:

...

Here is another 32-bit suse machine with 4 GB and the bigsmp kernel:

08:46 providence~> free -tm total used free shared buffers cached Mem: 3041 2103 938 0 502 1059 -/+ buffers/cache: 541 2500 Swap: 1027 0 1027 Total: 4069 2103 1965

Could you include a "uname -a" output just as a sanity check?

If this machine is actually hiding a gig, that's pathological. Do tell the hardware details...

Joe

Sorry to omit is, but yep! 01:07 providence~> uname -a Linux providence 2.6.22.17-0.1-bigsmp #1 SMP 2008/02/10 20:01:04 UTC i686 i686 i386 GNU/Linux Pathological -- maybe; Certifiable -- definitely! -- David C. Rankin, J.D., P.E. Rankin Law Firm, PLLC 510 Ochiltree Street Nacogdoches, Texas 75961 Telephone: (936) 715-9333 Facsimile: (936) 715-9339 www.rankinlawfirm.com -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The Saturday 2008-02-23 at 17:21 -0500, Charles philip Chan wrote:

...

"Some chipsets don't actually allow access to the full 4 GB. This might be one of them."

This should work with cpu > Pentium Pro. It seems like the SuSE kernel

It is not a software issue. There are some boards that simply can not handle that much ram. It's a known issue. - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4-svn0 (GNU/Linux) iD8DBQFHwKrWtTMYHG2NR9URAvUFAJ9eDQRcih+OI7uVqE9pxkNix82Y0gCfYY+k iauxyWttdT4gBrU3Hak8fzE= =CRwH -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Charles philip Chan schrieb:

...

"Some chipsets don't actually allow access to the full 4 GB. This might be one of them."

This should work with cpu > Pentium Pro. It seems like the SuSE kernel is still compiled with the 3GB/1GB split instead of using the 4GB or 64GB (PAE) option. I don't use a default SuSE kernel here- can someone comfirm this?

AFAIK in flat memory model on a 32-bit system the cpu, chipset and the kernel supports only 32 bit addressing. In an PAE model (Physical Address Extension) on a 32 bit system the cpu (since petium pro), the chipset and the kernel must support the 36 addressing. A 32 bit addressing can address 2^32 byte of physical memory. A 36 bit addressing can address 2^36 byte of physical memory. A 64 bit addressing can address 2^62 byte of physical memory. AFAIK all current chipsets shall support per se the 36 bit addressing extension of a current cpu. Thus I'm concluding if it doesn't work then it might be a BIOS issue. Furthermore when using 36 bit addressing the addresses got to be translated (paging translation) which makes it way slower then using a native 64 bit addressing on a 64-bit system. In PAE the operating system uses page tables to map this 4 GiB address space onto the 64 GiB of total memory, and the map is usually different for each process. More to be found here: http://en.wikipedia.org/wiki/Physical_Address_Extension or here: http://www.x86.org/articles/2mpages/2mpages.htm - -- All the best, Peter J. P-N. aedon DESIGNS http://www.hochzeitsbuch.info/ http://www.aedon.eu/ -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4-svn0 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iD8DBQFHwQ99h8q3OtgoGAwRAj6eAJ4342XydeJXeAsJQI79i6WnIaqcWQCeO5uK 4LGcxNiMpPD7Lk1ATDa9ZYg= =Koj0 -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org

Thus I'm concluding if it doesn't work then it might be a BIOS issue.

Once again: - The Bios has to reserve address space for PCI devices and usually reserves between 0.5 and 1 GiB. - To make the physical RAM that's hidden by that reservation available, most BIOSs map this RAM beyond the 4 GiB (2^32) Threshold. - To address that memory, you need a kernel supporting either PAE or long (i.e. 64 bit) mode. If the memory isn't available, it's rather obvious that it is the BIOS that failed to do the mapping.

In PAE the operating system uses page tables to map this 4 GiB address space onto the 64 GiB of total memory, and the map is usually different for each process.

You've got something mixed up there. Not the OS but the processor uses page tables and it does that for *all* operating modes, not only PAE, as virtual memory management on x86 and x86-64 relies on page tables. Philipp -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org

* Joe Sloan [02-20-08 20:54]:

John Andersen wrote:

...

On Wed, Feb 20, 2008 at 12:26 PM, Andrei Verovski (aka MacGuru)

The proper kernel for that machine is the x86_64, NOT 32 bit.

It will give access to all your memory and about a 20 to 30% speed boost with a typical mix of software.

Perhaps - and lots of problems with multimedia and 3rd party apps...

I guess ummv :^) I have x86_64 and except for FireFox, java and ff plugins am all 64 bit and have no problems. But I must watch that updates do not try to install 32 bit packages. -- Patrick Shanahan Plainfield, Indiana, USA HOG # US1244711 http://wahoo.no-ip.org Photo Album: http://wahoo.no-ip.org/gallery2 Registered Linux User #207535 @ http://counter.li.org -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org

Randall R Schulz wrote:

On Wednesday 20 February 2008 14:51, John Andersen wrote:

...

On Wed, Feb 20, 2008 at 12:26 PM, Andrei Verovski (aka MacGuru)

wrote:

...

Hi !

I have PC box with Core 2 Quad, P35 chipset and 4 GB of RAM (2+2 GB) with 32-bit OpenSuSE 10.3 and kernel-default installed. Why did you do that?

The proper kernel for that machine is the x86_64, NOT 32 bit.

These processors work just fine in 32-bit mode and support PAE in that mode.

...

It will give access to all your memory and about a 20 to 30% speed boost with a typical mix of software.

As we've been through this before, I'll just say that this is by no means the fact John presents it to be.

A better rule of thumb is never run a 64-bit processor for tasks that don't require the address space it affords.

Good advice - I've got a busy server at the office, with 4 CPUs and 16 GB RAM - it's running a 64 bit suse OS, and it really needs the bigger address space. OTOH after seeing 18 months of thoroughly unimpressive performance from the mail server on my home network, a machine with 1 GB RAM, I upgraded from suse 10.2/64 to suse 10.3/32 and it performs much better with the 32 bit OS. Use 64-bit where it makes sense: on a machine big enough to actually benefit from the 64 bit OS, where you don't depend on any 3rd party software that does not play well with 64 bits (been there, done that) Joe -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org