#!/bin/bashGaYLinux联盟
# ramdisk.shGaYLinux联盟
# A "ramdisk" is a segment of system RAM memoryGaYLinux联盟
#+ that acts as if it were a filesystem.GaYLinux联盟
# Its advantage is very fast access (read/write time).GaYLinux联盟
# Disadvantages: volatility, loss of data on reboot or powerdown.GaYLinux联盟
# less RAM available to system.GaYLinux联盟
#GaYLinux联盟
# What good is a ramdisk?GaYLinux联盟
# Keeping a large dataset, such as a table or dictionary on ramdiskGaYLinux联盟
#+ speeds up data lookup, since memory access is much faster than disk access. E_NON_ROOT_USER=70 # Must run as root.GaYLinux联盟
ROOTUSER_NAME=rootGaYLinux联盟
MOUNTPT=/mnt/ramdiskGaYLinux联盟
SIZE=2000 # 2K blocks (change as appropriate)GaYLinux联盟
BLOCKSIZE=1024 # 1K (1024 byte) block sizeGaYLinux联盟
DEVICE=/dev/ram0 # First ram deviceGaYLinux联盟
username=`id -nu` if [ "$username" != "$ROOTUSER_NAME" ]GaYLinux联盟
thenGaYLinux联盟
echo "Must be root to run \"`basename $0`\"."GaYLinux联盟
exit $E_NON_ROOT_USERGaYLinux联盟
fi if [ ! -d "$MOUNTPT" ] # Test whether mount point already there,GaYLinux联盟
then #+ so no error if this script is runGaYLinux联盟
mkdir $MOUNTPT #+ multiple times.GaYLinux联盟
fi dd if=/dev/zero of=$DEVICE count=$SIZE bs=$BLOCKSIZE # Zero out RAM device.GaYLinux联盟
mke2fs $DEVICE # Create an ext2 filesystem on it.GaYLinux联盟
mount $DEVICE $MOUNTPT # Mount it.GaYLinux联盟
chmod 777 $MOUNTPT # So ordinary user can access ramdisk. # However, must be root to unmount it.GaYLinux联盟
echo "\"$MOUNTPT\" now available for use."GaYLinux联盟
# The ramdisk is now accessible for storing files, even by an ordinary user.GaYLinux联盟
# Caution, the ramdisk is volatile, and its contents will disappearGaYLinux联盟
#+ on reboot or power loss.GaYLinux联盟
# Copy anything you want saved to a regular directory.GaYLinux联盟
# After reboot, run this script again to set up ramdisk.GaYLinux联盟
# Remounting /mnt/ramdisk without the other steps will not work.GaYLinux联盟
exit 0 |
