[cobalt-users] Making a swapfile

[Gerald Waugh <gwaugh@xxxxxxxxxxxxxxxxxxxxxxx>]

My system has 512MB memory,  I want a 1GB swapfile
This is the method I use to create the swapfile

#### look at meminfo ####
[root tmp]# cat /proc/meminfo
        total:    used:    free:  shared: buffers:  cached:
Mem:  529395712 521211904  8183808 83701760 375746560 16183296
Swap: 237297664  2347008 234950656
MemTotal:    516988 kB
MemFree:       7992 kB
MemShared:    81740 kB
Buffers:     366940 kB
Cached:       15804 kB
*SwapTotal:   231736 kB*
SwapFree:    229444 kB

#### Check current swaps ####
[root tmp]# cat /proc/swaps 
Filename                        Type            Size    Used    Priority
/dev/md6                        partition       231736  1804    -1

#### cd to /home/tmp ####
[root tmp]# cd /home/tmp

#### create the swap file, using dd insures no holes ####
[root tmp]# dd if=/dev/zero of=swapfile bs=1024 count=1048576
1048576+0 records in
1048576+0 records out

#### execute  'mkswap; ####
[root tmp]# /sbin/mkswap -c -v1 /home/tmp/swapfile
Setting up swapspace version 1, size = 1073737728 bytes

#### execute swapon (enable it) #####
[root tmp]# /sbin/swapon /home/tmp/swapfile

#### Check current swaps again ####
[root tmp]# cat /proc/swaps        [Current Swaps]
Filename                        Type            Size    Used    Priority
/dev/md6                        partition       231736  1804    -1
/home/tmp/swapfile              file            1048568 0       -2
#### I now have ~1.2 GB swap memory... ####

#### Now fix it so the swap file gets started on boot ####
[root tmp]# cp /etc/rc.d/rc.sysinit /etc/rc.d/rc.sysinit.save [backup]
[root tmp]# vi /etc/rc.d/rc.sysinit
#### look for these lines ####
# Start up swapping.
action "Activating swap partitions" swapon -a
#### comment out the line beginning with action ####
#### modify this section as ####
# Start up swapping.
#action "Activating swap partitions" swapon -a
action "Activating swap partitions" swapon -a swapon /home/tmp/swapfile
#### Save the file ####

#### DONE ####

#### look at meminfo ####
[root tmp]# cat /proc/meminfo
        total:    used:    free:  shared: buffers:  cached:
Mem:  529395712 522534912  6860800 82948096 377397248 15179776
Swap: 1311031296  2347008 1308684288
MemTotal:    516988 kB
MemFree:       6700 kB
MemShared:    81004 kB
Buffers:     368552 kB
Cached:       14824 kB
*SwapTotal:  1280304 kB*
SwapFree:   1278012 kB

it may slow your system down, but a slow system is better than a broken one 
(crash)!
And then it again it may never need that much swap memory, but if it does!!!

I have implemented the above on all of my RaQs

Gerald
-- 
http://frontstreetnetworks.com         http://raqware.com
229 Front Street, Ste C, New Haven, CT 06513-3203
                           Phone: 203-785-0699