Debian not using all available ram

Hi all,

I setup a Debian Perfect server a couple of years ago and we just caught recently that it is not utilizing all the available ram. This server (Dell 1750) has 2 gigs of ram which is verified by the lshw results below.

Code:

======== LSWH =========
root@mail:/etc/default# lshw -C memory
  *-firmware
       description: BIOS
       vendor: Dell Computer Corporation
       physical id: 0
       version: A12 (09/29/2006)
       size: 64KiB
       capacity: 4032KiB
       capabilities: isa pci pnp upgrade shadowing escd cdboot bootselect edd int13floppytoshiba int13floppy360 int13floppy1200 int13floppy720 int9keyboard int14serial int10video acpi usb ls120boot biosbootspecification netboot
  *-cache:0
       description: L1 cache
       physical id: 700
       size: 8KiB
       capacity: 8KiB
       capabilities: internal write-back data
  *-cache:1
       description: L2 cache
       physical id: 701
       size: 512KiB
       capacity: 1MiB
       capabilities: internal varies unified
  *-cache:0
       description: L1 cache
       physical id: 703
       size: 8KiB
       capacity: 8KiB
       capabilities: internal write-back data
  *-cache:1
       description: L2 cache
       physical id: 704
       size: 512KiB
       capacity: 1MiB
       capabilities: internal varies unified
  *-memory
       description: System Memory
       physical id: 1000
       slot: System board or motherboard
       size: 2GiB
     *-bank:0
          description: DIMM DDR Synchronous 266 MHz (3.8 ns)
          physical id: 0
          slot: DIMM_1A
          size: 1GiB
          width: 64 bits
          clock: 266MHz (3.8ns)
     *-bank:1
          description: DIMM DDR Synchronous 266 MHz (3.8 ns)
          physical id: 1
          slot: DIMM_1B
          size: 1GiB
          width: 64 bits
          clock: 266MHz (3.8ns)
     *-bank:2
          description: DIMM DDR Synchronous 266 MHz (3.8 ns) [empty]
          physical id: 2
          slot: DIMM_2A
          width: 64 bits
          clock: 266MHz (3.8ns)
     *-bank:3
          description: DIMM DDR Synchronous 266 MHz (3.8 ns) [empty]
          physical id: 3
          slot: DIMM_2B
          width: 64 bits
          clock: 266MHz (3.8ns)

free -m

Code:

root@mail:/etc/default# free -m
             total       used       free     shared    buffers     cached
Mem:           248        244          4          0          5         33
-/+ buffers/cache:        205         42
Swap:          484        175        309

We've tried putting mem=2048 in the grub file but that isn't working.

Code:

GRUB_DEFAULT=0
GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet"
#GRUB_CMDLINE_LINUX=""
GRUB_CMDLINE_LINUX="var1 var2 mem=2048m"

The uname info is:

Code:

root@mail:/etc/default# uname -a
Linux mail.pboss.com 2.6.32-5-686 #1 SMP Tue Mar 8 21:36:00 UTC 2011 i686 GNU/Linux

Is this a bigmem issue or does anyone have any other suggestions?

Thanks,
Ken

 

What's the output of

Code:

cat /proc/meminfo

?

 

Thanks falko,

Here's the info;

Code:

MemTotal:         254508 kB
MemFree:            6916 kB
Buffers:           14484 kB
Cached:            40984 kB
SwapCached:        45968 kB
Active:            98024 kB
Inactive:         121536 kB
Active(anon):      73864 kB
Inactive(anon):    90260 kB
Active(file):      24160 kB
Inactive(file):    31276 kB
Unevictable:           0 kB
Mlocked:               0 kB
HighTotal:             0 kB
HighFree:              0 kB
LowTotal:         254508 kB
LowFree:            6916 kB
SwapTotal:        496632 kB
SwapFree:         120488 kB
Dirty:                 4 kB
Writeback:             0 kB
AnonPages:        119220 kB
Mapped:             8300 kB
Shmem:                20 kB
Slab:              13832 kB
SReclaimable:       5348 kB
SUnreclaim:         8484 kB
KernelStack:        2480 kB
PageTables:         4340 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:      623884 kB
Committed_AS:    1220324 kB
VmallocTotal:     766108 kB
VmallocUsed:        9064 kB
VmallocChunk:     736976 kB
HardwareCorrupted:     0 kB
HugePages_Total:       0
HugePages_Free:        0
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:       4096 kB
DirectMap4k:       12124 kB
DirectMap4M:      249856 kB

 

The server is in fact using 248MB of RAM. Please double-check if there are really 2GB of RAM, and if so, if they are ok (maybe you need to replace it).

 

Thanks falko, we'll do. There truly is 2GB recognized by the bios. You can see in my first post for this thread, the lswh result for bank 0 and bank 1 have 1GB chips in them.

Cheers!
Ken

 

I personally believe it has to be a configuration or kernel issue. We took another PE1750 (identical) down to the data center with 4 gigs in it and pull the hard drives from the original server and put them in the other server. It is now reading 2GB. This is certainly better than 256meg, but doesn't explain why the O/S doesn't see all the memory... regardless of whether it can use it.

Thanks,
Ken

 

MYSTERY SOLVED!!!!

Hi all,

Been a while since I'd worked on this, but I decided to rebuild the original server that was brought back from the data center (the one reporting the 256megs) and figured out what was causing it. Someone flipped the "OS Install Mode" to "ON" in the BIOS. This limited the memory to 256megs. What a PITA!

Anyway, toggling that off and rebooting caused the OS to see all the memory.

Hope this helps someone else.

Cheers!
Ken