PERMANENTLY setting shmmax in Linux - Suse Personal Edition 8.2

linuxquestion_at_yahoo.com
Date: 12/18/03


Date: 17 Dec 2003 20:50:48 -0800

Ok, I have discovered the secret.

You may have noticed my other post on this subject. But,
it's so old that I can't post to it anymore. So the
solution is here.

-------------

Big picture.

This method uses sysctl. It does not use echo commands.
You only edit a few files, and reboot. Just like in Solaris.

You need to configure -FOUR- things. NO less.

/etc/init.d/boot.sysctl is a script.

/etc/init.d/boot.d is a directory.

/etc/sysctl.conf is a parameter file.

and then you have to create a link. I used:

/etc/init.d/boot.d/S20boot.sysctl

------------
Edit the file /etc/sysctl.conf, and insert the value
for shmmax into it.

cat /etc/sysctl.conf
kernel.shmmax=2147483648

before:
cat /proc/sys/kernel/shmmax
33554432

start sysctl:
/etc/init.d/boot.sysctl start

Setting current sysctl status from /etc/sysctl.conf
kernel.shmmax = 2147483648

after:
cat /proc/sys/kernel/shmmax
2147483648

ta da!

Now, you get this to run at boot time. (He, he, he.
We'll get that server to serve ME yet, instead of the
other way around!!!!)

------------

Create the link: /etc/init.d/boot.d/S20boot.sysctl

cd /etc/init.d/boot.d

total 8
drwxr-xr-x 2 root root 4096 Oct 19 19:20 .
drwxr-xr-x 11 root root 4096 Dec 17 21:39 ..
lrwxrwxrwx 1 root root 12 Oct 19 19:20 S01boot.proc
-> ../boot.proc
...
lrwxrwxrwx 1 root root 16 Oct 19 19:20
S10boot.ipconfig -> ../boot.ipconfig
lrwxrwxrwx 1 root root 12 Oct 19 19:20 S10boot.klog
-> ../boot.klog

ln -s /etc/init.d/boot.sysctl S20boot.sysctl

lrwxrwxrwx 1 root root 12 Oct 19 19:20 S10boot.klog
-> ../boot.klog
lrwxrwxrwx 1 root root 23 Dec 17 22:03 S20boot.sysctl
-> /etc/init.d/boot.sysctl

-------------

- reboot. It works!!!!!!! What a concept.

cat /proc/sys/kernel/shmmax
2147483648

------------

Later, I added more entries to /etc/sysctl.conf:

kernel.shmmax=2147483648
kernel.shmmni=4096
kernel.shmall=2097152
kernel.sem="250 32000 100 128"
kernel.hostname=white
fs.file-max=65536

reboot.

cat /proc/sys/kernel/shmmax
2147483648

cat /proc/sys/kernel/shmmni
4096

cat shmall
2097152

cat sem
250 32000 100 128

---------

So, it only took a month and a week to configure the
memory at boot time. I think that what caused problems
for me was that so much of the instructions that I found
either assumed a knowledge that I didn't have yet, or missed
one of the pieces or steps. Does not compute.

So, for those of you struggling with such simple
business, I hope this helps you. Please post your
solutions when you figure them out.