[SOLVED] RAM Recognition

jjleonb · #1 4th July 2012, 05:38 AM

Hi, I have a Fedora 15, kernel 2.6.43.8-1.fc15.i686. Everything is working properly except that since I have installed it, I have a RAM recognition issue. It shows 3GB instead of 8GB. I did what you suggest on the Fedora Documentation (Following this link http://docs.fedoraproject.org/en-US/...ouble-ram.html), but without succeed. The weard thing is that when hit dmesg | grep RAM, this is what it shows:
[root@localhost tux3]# dmesg | grep RAM
[ 0.000000] BIOS-provided physical RAM map:
[ 0.000000] user-defined physical RAM map:
[ 0.000000] total RAM covered: 7936M
[ 0.000000] gran_size: 64K chunk_size: 64K num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 64K chunk_size: 128K num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 64K chunk_size: 256K num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 64K chunk_size: 512K num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 64K chunk_size: 1M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 64K chunk_size: 2M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 64K chunk_size: 4M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 64K chunk_size: 8M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 64K chunk_size: 16M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 64K chunk_size: 32M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 64K chunk_size: 64M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 64K chunk_size: 128M num_reg: 8 lose cover RAM: 0G
[ 0.000000] gran_size: 64K chunk_size: 256M num_reg: 8 lose cover RAM: 256M
[ 0.000000] gran_size: 64K chunk_size: 512M num_reg: 8 lose cover RAM: 768M
[ 0.000000] *BAD*gran_size: 64K chunk_size: 1G num_reg: 8 lose cover RAM: -256M
[ 0.000000] gran_size: 64K chunk_size: 2G num_reg: 8 lose cover RAM: 256M
[ 0.000000] gran_size: 128K chunk_size: 128K num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 128K chunk_size: 256K num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 128K chunk_size: 512K num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 128K chunk_size: 1M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 128K chunk_size: 2M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 128K chunk_size: 4M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 128K chunk_size: 8M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 128K chunk_size: 16M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 128K chunk_size: 32M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 128K chunk_size: 64M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 128K chunk_size: 128M num_reg: 8 lose cover RAM: 0G
[ 0.000000] gran_size: 128K chunk_size: 256M num_reg: 8 lose cover RAM: 256M
[ 0.000000] gran_size: 128K chunk_size: 512M num_reg: 8 lose cover RAM: 768M
[ 0.000000] *BAD*gran_size: 128K chunk_size: 1G num_reg: 8 lose cover RAM: -256M
[ 0.000000] gran_size: 128K chunk_size: 2G num_reg: 8 lose cover RAM: 256M
[ 0.000000] gran_size: 256K chunk_size: 256K num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 256K chunk_size: 512K num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 256K chunk_size: 1M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 256K chunk_size: 2M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 256K chunk_size: 4M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 256K chunk_size: 8M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 256K chunk_size: 16M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 256K chunk_size: 32M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 256K chunk_size: 64M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 256K chunk_size: 128M num_reg: 8 lose cover RAM: 0G
[ 0.000000] gran_size: 256K chunk_size: 256M num_reg: 8 lose cover RAM: 256M
[ 0.000000] gran_size: 256K chunk_size: 512M num_reg: 8 lose cover RAM: 768M
[ 0.000000] *BAD*gran_size: 256K chunk_size: 1G num_reg: 8 lose cover RAM: -256M
[ 0.000000] gran_size: 256K chunk_size: 2G num_reg: 8 lose cover RAM: 256M
[ 0.000000] gran_size: 512K chunk_size: 512K num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 512K chunk_size: 1M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 512K chunk_size: 2M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 512K chunk_size: 4M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 512K chunk_size: 8M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 512K chunk_size: 16M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 512K chunk_size: 32M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 512K chunk_size: 64M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 512K chunk_size: 128M num_reg: 8 lose cover RAM: 0G
[ 0.000000] gran_size: 512K chunk_size: 256M num_reg: 8 lose cover RAM: 256M
[ 0.000000] gran_size: 512K chunk_size: 512M num_reg: 8 lose cover RAM: 768M
[ 0.000000] *BAD*gran_size: 512K chunk_size: 1G num_reg: 8 lose cover RAM: -256M
[ 0.000000] gran_size: 512K chunk_size: 2G num_reg: 8 lose cover RAM: 256M
[ 0.000000] gran_size: 1M chunk_size: 1M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 1M chunk_size: 2M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 1M chunk_size: 4M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 1M chunk_size: 8M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 1M chunk_size: 16M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 1M chunk_size: 32M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 1M chunk_size: 64M num_reg: 8 lose cover RAM: 832M
[ 0.000000] gran_size: 1M chunk_size: 128M num_reg: 8 lose cover RAM: 0G
[ 0.000000] gran_size: 1M chunk_size: 256M num_reg: 8 lose cover RAM: 256M
[ 0.000000] gran_size: 1M chunk_size: 512M num_reg: 8 lose cover RAM: 768M

[ 0.000000] gran_size: 1G chunk_size: 1G num_reg: 4 lose cover RAM: 1792M
[ 0.000000] gran_size: 1G chunk_size: 2G num_reg: 4 lose cover RAM: 1792M
[ 0.000000] gran_size: 2G chunk_size: 2G num_reg: 2 lose cover RAM: 3840M
[ 0.000000] RAMDISK: 370e6000 - 37ff0000
[ 0.000000] Allocated new RAMDISK: 361dc000 - 370e5b0e
[ 0.000000] Move RAMDISK from 00000000370e6000 - 0000000037fefb0d to 361dc000 - 370e5b0d
[ 0.160458] reserve RAM buffer: 000000000009fc00 - 000000000009ffff
[ 0.160460] reserve RAM buffer: 00000000c3780000 - 00000000c3ffffff

The results show that in some part of the booting procedure it has recognized all my RAM. But after booting up completely I only have 3G left.

Apparently it'is a RAM Issue (but I'm a newbie) but that's what it shows the command.
After booting up this is what I have in my /proc/meminfo

[root@localhost tux3]# cat /proc/meminfo
MemTotal: 3160796 kB
MemFree: 2150700 kB
Buffers: 38968 kB
Cached: 583088 kB
SwapCached: 0 kB
Active: 485960 kB

SwapTotal: 5242876 kB
SwapFree: 5242876 kB
Dirty: 28 kB
Writeback: 0 kB
AnonPages: 306164 kB
Mapped: 92824 kB
Shmem: 138712 kB
Slab: 41900 kB
SReclaimable: 17196 kB
SUnreclaim: 24704 kB
KernelStack: 2224 kB
PageTables: 3120 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
WritebackTmp: 0 kB
CommitLimit: 6823272 kB
Committed_AS: 1381868 kB
VmallocTotal: 122880 kB
VmallocUsed: 37564 kB
VmallocChunk: 66704 kB
HardwareCorrupted: 0 kB
AnonHugePages: 86016 kB
HugePages_Total: 0
HugePages_Free: 0
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 4096 kB
DirectMap4k: 16376 kB
DirectMap4M: 888832 kB

And this is the result after df -h
Filesystem Size Used Avail Use% Mounted on
rootfs 50G 4.9G 43G 11% /
udev 1.5G 4.0K 1.5G 1% /dev
tmpfs 1.6G 380K 1.6G 1% /dev/shm
tmpfs 1.6G 676K 1.6G 1% /run
/dev/mapper/VolGroup-lv_root
50G 4.9G 43G 11% /
tmpfs 1.6G 0 1.6G 0% /sys/fs/cgroup
tmpfs 1.6G 676K 1.6G 1% /var/run
tmpfs 1.6G 676K 1.6G 1% /var/lock
tmpfs 1.6G 0 1.6G 0% /media
/dev/sda1 497M 90M 383M 19% /boot
/dev/mapper/VolGroup-lv_home
410G 26G 364G 7% /home

Any suggestions would be very appreciated.

Thanks in advance.

BBQdave · #2 4th July 2012, 05:52 AM

Quote:

Originally Posted by jjleonb

Hi, I have a Fedora 15, kernel 2.6.43.8-1.fc15.i686. Everything is working properly except that since I have installed it, I have a RAM recognition issue. It shows 3GB instead of 8GB.

Interesting, kernel 2.6.43.8-1.fc15.i686 should recognize your RAM. F15 is at EOL, if you have the chance to try Fedora 17, that may resolve your RAM recognition issue - you could test with the live cd before full install.

***DBelton*** · #3 4th July 2012, 07:28 AM

No, kernel 2.6.43.8-1.fc15.i686 WILL NOT recognize all of the RAM. That is a 32 bit kernel, and will recognize 4GB maximum. That is 4GB minus what is used to map the devices into address spaces below 4GB.

You will have to install the PAE kernel or reinstall Fedora using the x86_64 kernel to recognize all of the 8GB of RAM.

george_toolan · #4 4th July 2012, 08:27 AM

You can test your RAM with Memtest86+, but if you want to use more than about 3 GiB, you'll have to use a PAE kernel or install a 64 bit operation system, because a 32 bit operating system only has 4 GiB address space.

If you install a PAE kernel then a single process cannot use more than 3 GiB of memory. If it tries to get more memory it will crash ;-)

jjleonb · #5 6th July 2012, 12:02 AM

Hi, thanks all of you to make this works, finally it has recognized all the RAM memory (8 GB), as I installed the kernel-PAE (yum install kernel-PAE), it works like heaven.

***DBelton*** · #6 6th July 2012, 01:49 AM

Installing the PAE kernel was the option that would have been the least mount of work on your part

You probably would actually be better off doing a complete re-install and getting the x86_64 version as there are other benefits to running a full 64 bit kernel over the PAE kernel, but for now, the PAE will work fine for you.

Just remember that the next time you decide to do a complete install on that machine, and get the x86_64 version instead of the i686 version.

Actually, the install should have installed the PAE kernel for you by default since you have over 4GB of RAM. Was all of your RAM installed when you went through the Fedora install?

Also, if you had the kernel-devel package installed before, you need to install the kernel-PAE-devel package. If you didn't need the kernel-devel package, then you really don't have to install the PAE version.

***Gareth Jones*** · #7 6th July 2012, 06:24 PM

Yes, unless there are specific reasons for needing a 32-bit system, it is almost always best to run 64-bit on a 64-bit-capable system, at least with Linux-based OSes. Remember that PAE, irrespective of the OS used, will never let an individual program use more than 1/2/3 GiB of memory (depending on the kernel settings) – only proper 64-bit allows that.