RamFS for /private/tmp

RamFS

#!/bin/sh
# Create a RAM disk with same perms as mountpoint

RAMDisk() {
    mntpt=$1
    rdsize=$(($2*1024*1024/512))
    echo "Creating RamFS for $mntpt"
    # Create the RAM disk.
    dev=`hdik -drivekey system-image=yes -nomount ram://$rdsize`
    # Successfull creation…
    if [ $? -eq 0 ] ; then
        # Create HFS on the RAM volume.
        newfs_hfs $dev
        # Store permissions from old mount point.
        eval `/usr/bin/stat -s $mntpt`
        # Mount the RAM disk to the target mount point.
        mount -t hfs -o union -o nobrowse $dev $mntpt
        # Restore permissions like they were on old volume.
        chown $st_uid:$st_gid $mntpt
        chmod $st_mode $mntpt
    fi
}

# Test for arguments.
if [ -z $1 ]; then
    echo "Usage: $0 [start|stop|restart] "
    exit 1
fi

# Source the common setup functions for startup scripts
test -r /etc/rc.common || exit 1 
. /etc/rc.common

StartService () {
    ConsoleMessage "Starting RamFS disks…"
    RAMDisk /private/tmp 256
    RAMDisk /var/run 64
   # RAMDisk /var/db 1024
   # mkdir -m 1777 /var/db/mds
}
StopService () {
    ConsoleMessage "Stopping RamFS disks, nothing will be done here…"
    # diskutil unmount /private/tmp /private/var/run
    # diskutil unmount /private/var/run
}

RestartService () {
    ConsoleMessage "Restarting RamFS disks, nothing will be done here…"
}

RunService "$1"

StartupParameters.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist SYSTEM "file://localhost/System/Library/DTDs/PropertyList.dtd">
<plist version="0.9">
    <dict>
        <key>Description</key>
        <string>RamFS Disks Manager</string>
        <key>OrderPreference</key>
        <string>Early</string>
        <key>Provides</key>
        <array>
                <string>RamFS</string>
        </array>
        <key>Uses</key>
        <array>
                <string>Disks</string>
        </array>
    </dict>
</plist>

-rwxr-xr-x 1 root wheel 1383 7 Jun 13:56 RamFS
-rw-r--r-- 1 root wheel 510 7 Jun 13:55 StartupParameters.plist