FC6 - 64-bit, 16GB RAM not recognized

[Whoopi_Cat]

All,


I have a user who's only seeing 11 of his 16GB RAM after boot. This is FC6 x86_64.

uname-a =

2.6.19-1.2911.fc6 #1 SMP Sat Feb 10 15:16:31 EST 2007 x86_64 x86_64 x86_64 GNU/Linux

It states quite clearly in /var/log/messages (below) that I'm not getting it all. You can see that I specify 16GB on the kernel boot line.

Any suggestions on how to get the other 5GB?

Thanks


Feb 22 10:52:58 coil3 kernel: Kernel command line: mem=16000m ro root=LABEL=/1 rhgb
Feb 22 10:52:58 coil3 kernel: Memory: 11077076k/16384000k available (2468k kernel code, 211048k reserved, 1938k data, 312k init)
Feb 22 10:52:58 coil3 kernel: Freeing initrd memory: 1606k freed
Feb 22 10:52:58 coil3 kernel: MEM window: fa700000-fa8fffff
Feb 22 10:52:58 coil3 kernel: MEM window: fa500000-fa6fffff
Feb 22 10:52:58 coil3 kernel: MEM window: f9c00000-fa4fffff
Feb 22 10:52:58 coil3 kernel: MEM window: faa00000-feafffff
Feb 22 10:52:58 coil3 kernel: Total HugeTLB memory allocated, 0
Feb 22 10:52:58 coil3 kernel: Non-volatile memory driver v1.2
Feb 22 10:52:58 coil3 kernel: Freeing unused kernel memory: 312k freed
Feb 22 10:52:58 coil3 kernel: ohci_hcd 0000:03:00.0: irq 19, io mem 0xfa8fd000
Feb 22 10:52:58 coil3 kernel: ohci_hcd 0000:03:00.1: irq 19, io mem 0xfa8fe000

[wt6g]

I had to laugh at this one. I even tried to think up a funny analogy. Something along the lines of being married to some rich gorgeous starlet and complaining because she didn't do her hair before she came to bed every night, but then I decided not everyone would see the humor. Anyway, I might have a hint for you.

Grub forms several ram disks when Fedora boots (I think 16) and normally it does not reserve much memory for these according to one document I have (4 Mb), but it will if that is put on the command line. These ram disks are VERY useful for lots of tasks, and with 16GB of memory might be one thing for your user to investigate so he can actually use the memory (if thats not the problem).

Check out /boot/grub/grub.conf and see if you see ramdisk_size = xxxxxx xxxxx is in k bytes

I've got a system configured for 128 MB ramdisks but as I recall the memory isn't allocated to them (16 x 128 Mb of them to be exact can be found in /dev) unless I format them. It could be that your user has somehow got something in rc.local thats preparing or causing this memory to be allocated. Also be aware that the memory isn't given back even if you unmount them and the data on them remains until you reboot.

Len Umina
WT6G