How much memory is in this machine?
It would seem that answering this question ought to be easy; it is – but every system has the answer in a different place. Most put an answer of some sort into kernel messages reported by dmesg (AIX apparently does not).
Most systems have a program for system inventory which reports a variety of things, including memory.
Rather than go into great detail about each one, we’ll just put these out there for all of you to reference. Each environment has multiple commands that give available memory; each command is listed below.
Without further ado, here are a few answers to this burning question:
Solaris
dmesg | grep mem
prtdiag | grep Memory
prtconf -v | grep Memory
AIX
bootinfo -r
lsattr -E1 sys0 -a realmem
getconf REAL_MEMORY
HPUX
dmesg | grep Physical
/opt/ignite/bin/print_manifest | grep Memory
machinfo | grep Memory
Linux
dmesg | grep Memory
grep -i memtotal /proc/meminfo
free
OpenVMS
show mem /page
Update:
FreeBSD
dmesg | grep memory
grep memory /var/run/dmesg.boot
sysctl -a | grep mem
Sorry for the uber number of posts today. But if anyone is interested there is a c file on itrc that can be compiled to get some good memory info on hpux. Here is a link:
http://forums13.itrc.hp.com/service/forums/questionanswer.do?admit=109447627+1234982141646+28353475&threadId=1180784
You want the file memdetail.c
If you have OnlineDiag installed on your HP-UX box (and I really can’t think of why you wouldn’t), this is pretty handy in seeing memory information:
echo “selclass qualifier memory;info;wait;infolog” | /usr/sbin/cstm
I’d forgotten that utility. This information also can be gotten from /usr/sbin/mstm (text menu driven) and /usr/sbin/xstm (X display). I’m not sure if the others are scriptable like this; I think they may all be the same binary.
AIX:
lsattr -E1 sys0 -a realmem
should not be a 1, but rather:
lsattr -El sys0 -a realmem
Linux
cat /proc/meminfo
If you are running a non-PAE kernel the mentioned Linux commands don’t give you the full picture.
In that case you can try to make sense of the output of
dmidecode -t memory