# Available Memory != Real Memory



## mohenh (Mar 5, 2014)

Hi,

I've had this issue on some of my machines. I can't seem to have freebsd FreeBSD recognize and use the installed memory. I've installed 22 GB DDR2 ECC RAM and the system can only use 8 GB of it. Here are the specifics: I've tried different RAM modules and different configurations but I could not get the system to recognize more than 8 GB of RAM on it.

This is the MB motherboard: http://www.supermicro.com/Aplus/motherb ... 8QM8-2.cfm

Thanks*.*


```
FreeBSD 10.0-RELEASE #0 r260789: Thu Jan 16 22:34:59 UTC 2014
    root@snap.freebsd.org:/usr/obj/usr/src/sys/GENERIC amd64
FreeBSD clang version 3.3 (tags/RELEASE_33/final 183502) 20130610
CPU: Quad-Core AMD Opteron(tm) Processor 8356 (2311.90-MHz K8-class CPU)
  Origin = "AuthenticAMD"  Id = 0x100f22  Family = 0x10  Model = 0x2  Stepping = 2
  Features=0x178bfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,MMX,FXSR,SSE,SSE2,HTT>
  Features2=0x802009<SSE3,MON,CX16,POPCNT>
  AMD Features=0xee500800<SYSCALL,NX,MMX+,FFXSR,Page1GB,RDTSCP,LM,3DNow!+,3DNow!>
  AMD Features2=0x7ff<LAHF,CMP,SVM,ExtAPIC,CR8,ABM,SSE4A,MAS,Prefetch,OSVW,IBS>
  TSC: P-state invariant
real memory  = 21474836480 (20480 MB)
avail memory = 7356461056 (7015 MB)
Event timer "LAPIC" quality 400
ACPI APIC Table: <A M I  OEMAPIC >
FreeBSD/SMP: Multiprocessor System Detected: 16 CPUs
FreeBSD/SMP: 4 package(s) x 4 core(s)
```


```
./freebsd-memory 
SYSTEM MEMORY INFORMATION:
mem_wire:         955170816 (    910MB) [ 12%] Wired: disabled for paging out
mem_active:  +   4749623296 (   4529MB) [ 64%] Active: recently referenced
mem_inactive:+   1536970752 (   1465MB) [ 20%] Inactive: recently not referenced
mem_cache:   +     72802304 (     69MB) [  0%] Cached: almost avail. for allocation
mem_free:    +     89882624 (     85MB) [  1%] Free: fully available for allocation
mem_gap_vm:  +       520192 (      0MB) [  0%] Memory gap: UNKNOWN
-------------- ------------ ----------- ------
mem_all:     =   7404969984 (   7061MB) [100%] Total real memory managed
mem_gap_sys: +    218984448 (    208MB)        Memory gap: Kernel?!
-------------- ------------ -----------
mem_phys:    =   7623954432 (   7270MB)        Total real memory available
mem_gap_hw:  +    965980160 (    921MB)        Memory gap: Segment Mappings?!
-------------- ------------ -----------
mem_hw:      =   8589934592 (   8192MB)        Total real memory installed

SYSTEM MEMORY SUMMARY:
mem_used:        6890278912 (   6571MB) [ 80%] Logically used memory
mem_avail:   +   1699655680 (   1620MB) [ 19%] Logically available memory
-------------- ------------ ----------- ------
mem_total:   =   8589934592 (   8192MB) [100%] Logically total memory
```


----------



## mohenh (Mar 7, 2014)

I'm really puzzled by this issue. I appreciate any help anyone could give me. Perhaps tell me what could be the issue or what to check to get an idea of what's gone wrong.

Thanks.


----------



## trh411 (Mar 7, 2014)

Is there a BIOS/firmware upgrade available for that motherboard? I've seen some really strange problems (and this certainly qualifies) that were resolved with upgrades.


----------



## donkeyofdarkness (Mar 8, 2014)

The ram is bad

The RAM is bad.


----------



## phartbut (Mar 8, 2014)

No, I had this exact board and also had this problem. Supermicro said the memory controller was bad on some boards of this model. They sent me a replacement for free. If you contact them they will let you RMA it. The new motherboard works fine. the BIOS update does not address this issue.


----------



## mohenh (Mar 8, 2014)

I did the BIOS update with no success. The board is a few years old and I'm not sure if Supermicro would be able to help with it.

I will try to get in touch with Supermicro, thanks for the suggestion. It's the first time I have had to deal with something like this.

Thanks.


----------

