Hi,

I finally got around to compiling a Kernel - 2.6.12.3 under slackware current.

As I have 1 Gig RAM I enabled Himem support.

Everything is running fine but the amount of memory reported seems slightly short of a gigabyte.

andrew@foobar:~$ free -t
total used free shared buffers cached
Mem: 1035532 441632 593900 0 45708 277008
-/+ buffers/cache: 118916 916616
Swap: 658656 0 658656
Total: 1694188 441632 1252556

and

andrew@foobar:~$ cat /proc/meminfo
MemTotal: 1035532 kB
MemFree: 543284 kB
Buffers: 55796 kB
Cached: 293176 kB
SwapCached: 0 kB
Active: 237188 kB
Inactive: 216568 kB
HighTotal: 131008 kB
HighFree: 120 kB
LowTotal: 904524 kB
LowFree: 543164 kB
SwapTotal: 658656 kB
SwapFree: 658656 kB
Dirty: 20 kB
Writeback: 0 kB
Mapped: 163120 kB
Slab: 29052 kB
CommitLimit: 1176420 kB
Committed_AS: 242960 kB
PageTables: 1508 kB
VmallocTotal: 114680 kB
VmallocUsed: 4688 kB
VmallocChunk: 109944 kB

I was under the impression that I had 1048576 kB of RAM.
Is my memory borked, is this a quirk of linux or is there some other explanation? I've had a quick look but found no obvious explanations , but feel I'm missing something obvious

Thanks in advance

You could always run memtest86+ which would advise you if your memory was OK.

samac

I think that /proc/meminfo and free don't report memory that the kernel has permanently allocated for itself (i.e. can never be released without crashing the kernel). This is why memory totals are always a little short (regardless of mem size). I've never bothered to actually poke deeper and try to verify this, though.

Thanks for the answers

The memory being allocated to the kernel sounds logical, and its still beats the amount reported before I recompiled the kernel.

I think my memory is ok (ran a quick memtest86 - obviously need to run a more thorough one later), also I run CPDN under windoze at the moment, and that is a pretty good test of reliability of your memory.

(Will switch CPDN to Slackware when my present run is finished)

BTW: couldn't have done the compile successfully without the guides here