topic Re: Memory after recompiling kernel in Operating System - Linux

Memory after recompiling kernel

mjsunil — Thu, 04 Mar 2004 02:51:41 GMT

Hi,
I had recomplied AS 2.1 kernel 2.4.9-e.3 to 2.4.9-e.24 in Compaq DL580. Now I noticed that the total memory shown in /proc/meminfo is only "919994368". any idea why this is so?pls help

Re: Memory after recompiling kernel

Claudio Cilloni — Thu, 04 Mar 2004 03:40:06 GMT

what is the total memory shown with the previous kernel? how much memory had you 'loose'?

Maybe you have compiled into the new kernel more modules than in the previous, so the kernel itself is bigger. Remember that new kernel versions can reserve more memory for their internal use.

Ciao
Claudio

Re: Memory after recompiling kernel

mjsunil — Thu, 04 Mar 2004 04:04:22 GMT

Hi Claudio,
The oroginal kernel 2.4.9-e.3 shows 2GB. I compiled all options into the kernel instead of modules.Is that the reason why the total memory is displayed as 919MB instead of 2GB?
rgds
mjs

Re: Memory after recompiling kernel

Claudio Cilloni — Thu, 04 Mar 2004 05:03:44 GMT

oops... the loss of 1GB+ of RAM goes beyond what I guessed...

Now I have no ideas... it is really weird. could you show the full content of /proc/meminfo?

Re: Memory after recompiling kernel

mjsunil — Thu, 04 Mar 2004 06:28:09 GMT

Hi here is the details frm /proc/meminfo
total: used: free: shared: buffers: cached:
Mem: 919994368 855797760 64196608 42569728 47906816 680173568
Swap: 2147442688 1392812032 754630656
MemTotal: 898432 kB
MemFree: 62692 kB
MemShared: 41572 kB
Buffers: 46784 kB
Cached: 80392 kB
SwapCached: 583840 kB
Active: 603296 kB
Inact_dirty: 120484 kB
Inact_clean: 28808 kB
Inact_target: 224584 kB
HighTotal: 0 kB
HighFree: 0 kB
LowTotal: 898432 kB
LowFree: 62692 kB
SwapTotal: 2097112 kB
SwapFree: 736944 kB
BigPagesFree: 0 kB

rgds
mjs

Re: Memory after recompiling kernel

Robert Binkhorst — Thu, 04 Mar 2004 07:02:36 GMT

Hi,

When you do a "grep -i memory /var/log/dmesg", what amount does it return?

HTH,

Robert

Re: Memory after recompiling kernel

mjsunil — Thu, 04 Mar 2004 07:15:51 GMT

Hi Robert,
Thks for the quick reply,here is the output of the command
Memory: 890892k/917504k available (2498k kernel code, 19156k reserved, 137k dat)
agpgart: Maximum main memory to use for agp memory: 816M
Freeing initrd memory: 102k freed
Freeing unused kernel memory: 368k freed

rgds
mjs

Re: Memory after recompiling kernel

mjsunil — Thu, 04 Mar 2004 07:29:54 GMT

Hi,I also tried grep -i agp /var/log/dmesg
and got the output
Linux agpgart interface v0.99 (c) Jeff Hartmann
agpgart: Maximum main memory to use for agp memory: 816M
agpgart: no supported devices found.
[drm] The i810 drm module requires the agpgart module to function correctly
Please load the agpgart module before you load the i810 module
It seems that we dont have a agp device in the server
rgds
mjs

Re: Memory after recompiling kernel

mjsunil — Thu, 04 Mar 2004 07:47:49 GMT

Hi, Is there any way to release the 816 MB of memory which is locked with agp?
rgds
mjs

Re: Memory after recompiling kernel

Robert Binkhorst — Thu, 04 Mar 2004 07:51:26 GMT

I would think you'd have to change those settings in 2 places:
- the bios
- the kernel configuration

Remove the drivers you don't need from the kernel, but I don't think that the agp driver is using 816Mb, though that's just a feeling.

Re: Memory after recompiling kernel

Robert Binkhorst — Thu, 04 Mar 2004 07:52:50 GMT

While you're in the bios, check the amount of memory that is reported/checked at boot and how much memory is reported in the bios.

Re: Memory after recompiling kernel

Claudio Cilloni — Thu, 04 Mar 2004 08:04:24 GMT

Maybe the kernel 2.4.9-e.24 has some incompatibility bug with your hardware. I think it worth trying a newer version or an intermediate version between 2.4.9-e.3 and this. Just guessing...

Ciao
Claudio

Re: Memory after recompiling kernel

Vitaly Karasik_1 — Thu, 04 Mar 2004 09:25:36 GMT

- first at all, the latest recommended by RH kernel for RHEL2.1 is 2.4.9-38

- and if you sure in 200% you need to recompile kernel, I suggest to take one of RH configs from /usr/src/linux2-4/configs as base for your kernel.

Re: Memory after recompiling kernel

mjsunil — Fri, 05 Mar 2004 00:04:18 GMT

Hi,I tried to boot with the old kernel which shows 2GB RAM. I guess I have to remove the agp part from the kernel and recompile, which i cant do just now. Thks for the help I will wait till I recompile to e.35 soon.
rgds
mjs