linux-kernel - Re: Missing RAM on x86

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20070604191347.GE10008@csclub.uwaterloo.ca>
Date:	Mon, 4 Jun 2007 15:13:47 -0400
From:	lsorense@...lub.uwaterloo.ca (Lennart Sorensen)
To:	Mike Richards <mrmikerich@...il.com>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: Missing RAM on x86_64

On Sat, Jun 02, 2007 at 12:51:07AM -0400, Mike Richards wrote:
> Hi, I appear to be missing quite a bit of RAM on an x86_64 system. I
> have 1GB installed, but 'free' only shows 878MB:
> 
> pokey$ free -m
>             total       used       free     shared    buffers     cached
> Mem:           878        571        306          0         52        332
> -/+ buffers/cache:        186        691
> Swap:         1023          0       1023
> 
> I'm used to seeing a little bit of RAM missing with 32bit systems, but
> 146MB seems a bit much. The part of dmesg that concerns the RAM is
> shown below. Anyone know what's up here? Is this normal for an x86_64
> system?

I you running a 64 or 32bit kernel?  If it is 32bit then it is normal
for a kernel not configured with CONFIG_4GB or whatever it is called to
be limited to about 900MB ram.  64bit kernels should see all the ram no
matter what the config is.  It looks very much like you are running a
32bit kernel though.  What does uname -a say?

--
Len Sorensen
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/