fedora 13 doesnt recognize all my ram!

romulusvii · #1 9th June 2010, 12:54 AM

running fedora 13 on an xfx 750a mother board and i have 8 gigs of ram and id really like to stick with fedora please help

#2 9th June 2010, 12:59 AM

Quote:

Originally Posted by romulusvii

running fedora 13 on an xfx 750a mother board and i have 8 gigs of ram and id really like to stick with fedora please help

have you got F13 64bit? the PAE kernel will recognise it all

GoinEasy9 · #3 9th June 2010, 01:23 AM

PAE kernels come as default on most (if not all) 32 bit installs, the PAE kernel will recognize 8 GB. The 64 bit kernel will also recognize 8GB. Why do you think Fedora is not seeing all 8GB?

diamond_ramsey · #4 9th June 2010, 01:51 AM

romulusvii, thank you for your post.

Quote:

Originally Posted by romulusvii

running fedora 13 on an xfx 750a mother board and i have 8 gigs of ram and id really like to stick with fedora please help

Hmmh, interesting.

===================================
I concur with GoinEasy9, why do you think your system is not accessing the 8 GB of RAM?

===================================
How's this, please run the following two commands as root:

cat /proc/meminfo|grep MemTotal

and

uname -r
===================================
The following are my values for comparative purposes.

[root@localhost ~]# cat /proc/meminfo|grep MemTotal
MemTotal: 3097368 kB

[root@localhost ~]# uname -r
2.6.33.4-96.fc13.i686.PAE
===================================
Hope this helps.

Marcus78 · #5 9th June 2010, 04:17 AM

I'm using 64-bit version of FC13 and I have no problems with 8Gb of memory. Having 4Gb+ you must
usually use 64-bit OS to get all the RAM fully usable.

uname -a

Linux ladybird 2.6.33.5-112.fc13.x86_64 #1 SMP Thu May 27 02:28:31 UTC 2010 x86_64 x86_64 x86_64 GNU/Linux

GoinEasy9 · #6 9th June 2010, 04:23 AM

@Marcus78 PAE works fine accessing over 4gb on 32 bit.

[root@Fedora14dw32 GoinEasy9]# cat /proc/meminfo|grep MemTotal
MemTotal: 4122124 kB
[root@Fedora14dw32 GoinEasy9]# uname -a
Linux Fedora14dw32 2.6.34-20.fc14.i686.PAE #1 SMP Wed Jun 2 12:53:34 UTC 2010 i686 i686 i386 GNU/Linux

Marcus78 · #7 9th June 2010, 04:37 AM

Quote:

Originally Posted by GoinEasy9

@Marcus78 PAE works fine accessing over 4gb on 32 bit.

[root@Fedora14dw32 GoinEasy9]# cat /proc/meminfo|grep MemTotal
MemTotal: 4122124 kB
[root@Fedora14dw32 GoinEasy9]# uname -a
Linux Fedora14dw32 2.6.34-20.fc14.i686.PAE #1 SMP Wed Jun 2 12:53:34 UTC 2010 i686 i686 i386 GNU/Linux

Yes I know how it works.

To romulusvii:

One possible solution could be if you add:

append mem=8192M

to /boot/grub/grub.conf at the end of the kernel -line.

That worked long time ago. And it seems that you're running PAE kernel anyways so it should
regonise all the memory but there must be some missing parameter in somewhere.

romulusvii · #8 9th June 2010, 03:49 PM

well since im still not too familiar with linux (only 16 barely getting into heavy linux usage) still dont know where to look but ill run MemTotal and see what it brings up will keep you posted if it works thanks

BugRocks1 · #9 9th June 2010, 04:56 PM

Please check the BIOS first to see if it is seeing all the memory there and look for some settings that may look like these:

IOMMU, Memory Mapping, Memory Remaping, Memory Mapped I/O, Memory Hole, Addres Mapping,

http://en.wikipedia.org/wiki/Memory-mapped_I/O
http://en.wikipedia.org/wiki/IOMMU
http://en.wikipedia.org/wiki/3_GB_barrier (most relevant read)

---------- Post added at 07:54 AM CDT ---------- Previous post was at 07:50 AM CDT ----------

Also your chipset may be the limiting factor:

http://www.memoryupgrade.pro/intel-c...m-memory1.html

Quote:

1 Lakeport chipsets lacks support for remapping memory; the size of addressable memory space may be less than 4GB, regardless whether the processor operates in 64-bit mode.

---------- Post added at 07:56 AM CDT ---------- Previous post was at 07:54 AM CDT ----------

http://www.google.com/search?q=Lakep...mapping+memory

Zanpactou · #10 9th June 2010, 08:05 PM

Quote:

Originally Posted by GoinEasy9

PAE kernels come as default on most (if not all) 32 bit installs, the PAE kernel will recognize 8 GB. The 64 bit kernel will also recognize 8GB. Why do you think Fedora is not seeing all 8GB?

I have to say here that my personal experience of config PAE = y in the Linux kernel results in an un-bootable system for my Asus Pentium M laptop. I have the 400 MHz bus version of the Pentium M. So enabling the physical address extension in 32 bit kernels is not being done by default and rightly so. I wouldn't be able to boot Fedora.
The PAE kernels are provided as a separate option.
http://en.wikipedia.org/wiki/Physical_Address_Extension

romulusvii, I think an memtest will expose how much RAM is being detected and if any is damaged.
IIRC you will find memtest on the boot menu of any Fedora live cd.

Code:

su -
yum -y install kernel-PAE
exit

Will install the PAE enabled Fedora Linux kernel.

Thanks,
Zanpactou

GoinEasy9 · #11 9th June 2010, 08:15 PM

@Zanpactou
I was just observing that on all my fresh 32 bit installs, PAE kernels were the default, in fact, the only way I got a non-PAE kernel was by mistakingly installing a graphics driver that had a non-PAE kernel as a dependency.

Zanpactou · #12 10th June 2010, 03:13 AM

Quote:

Originally Posted by GoinEasy9

@Zanpactou
I was just observing that on all my fresh 32 bit installs, PAE kernels were the default, in fact, the only way I got a non-PAE kernel was by mistakingly installing a graphics driver that had a non-PAE kernel as a dependency.

If PAE enabled kernels failing to boot on Pentium M machines has been fixed somewhere between 2.6.31 and 2.6.34, then your claim would seem to make sense.

We have a separate PAE kernel available to us and I own a machine which has never been able to boot a PAE enabled Linux kernel, yet I was able to boot the live cd and install Fedora, which I am posting back to you using now.
Every single PAE enabled Linux kernel that I have tried to boot on my machine gives me a very clear message at boot time that PAE is not supported by my machine's processor and then fails to proceed as a consequence.

The config for the last Fedora kernel I ran on my copy of Rawhide is : config-2.6.31.1-56.fc12.i686. And X86_PAE does not feature in that configuration file.
If X86_PAE exists and is set to Y in the config file for your current running Fedora kernel, which is located in the /boot directory, then PAE is enabled. Otherwise it is not.

Is it set in your config?

GoinEasy9 · #13 10th June 2010, 03:57 AM

@Zanpactou
I don't have anything set in config. All my installs are straight from DVD, and, except for choosing a custom partitioning setup, installs use all defaults. All of my 32 bit installs come with PAE by default, EXCEPT, when I installed rawhide, that came with a non-PAE kernel. I guess the installer is recognizing that PAE kernels aren't supported on your machine, so you are presented with a non-PAE kernel. I have to admit, this is the first time I've heard of a non-PAE kernel being installed by default on a 32 bit install. Starting back with my first install of Fedora (F11), every 32 bit default kernel was PAE.
The funny thing was when I yum updated from F13 to rawhide, the original F13 install had a PAE kernel, but when I upgraded that install to rawhide, it switched the kernel type to a non-PAE kernel. It's possible (maybe even likely) that the config for rawhide isn't set to install the PAE kernel. I don't know that as a fact, I've never looked into it.

romulusvii · #14 10th June 2010, 04:24 AM

Thanks for the help guys problem solved

had PAE kernel installed alredy just had to edit grub.conf file and worked perfectly

Zanpactou · #15 10th June 2010, 10:48 PM

Quote:

Originally Posted by GoinEasy9

@Zanpactou
I don't have anything set in config. All my installs are straight from DVD, and, except for choosing a custom partitioning setup, installs use all defaults. All of my 32 bit installs come with PAE by default, EXCEPT, when I installed rawhide, that came with a non-PAE kernel. I guess the installer is recognizing that PAE kernels aren't supported on your machine, so you are presented with a non-PAE kernel. I have to admit, this is the first time I've heard of a non-PAE kernel being installed by default on a 32 bit install. Starting back with my first install of Fedora (F11), every 32 bit default kernel was PAE.
The funny thing was when I yum updated from F13 to rawhide, the original F13 install had a PAE kernel, but when I upgraded that install to rawhide, it switched the kernel type to a non-PAE kernel. It's possible (maybe even likely) that the config for rawhide isn't set to install the PAE kernel. I don't know that as a fact, I've never looked into it.

Cool, I don't doubt it, I'm just interested now if things have changed because I could be looking at a machine that won't boot if I decide to re-install in future. I'll have to bare that in mind now because I could be looking at booting troubles if PAE is enabled now and it still means that my machine won't boot.

romulusvii,
glad you got it sorted.

Thanks,
Zanpactou