|Summary help replacing me|
|AUR (asd) is a tiny shell script designed to manage target directories in tmpfs and to periodically sync them back to your physical disc (HDD/SSD). This is accomplished via a symlinking step and an innovative use of rsync to maintain back-up and synchronization between the two. One of the major design goals of asd is a completely transparent user experience.|
Benefits of Asd
Running this daemon is beneficial for two reasons:
- Reduced wear to physical discs
Since the target directories are relocated into tmpfs, the corresponding onslaught of I/O associated with system usage of them is also redirected from the physical disc to RAM, thus reducing wear to the physical disc and also improving speed and responsiveness. The access time of RAM is on the order of nanoseconds while the access time of physical discs is on the order of milliseconds. This is a difference of six orders of magnitude or 1,000,000 times faster.
Setup and Installation
AUR. Build it and install like any other package.AUR is available for download from the
Edit the included
/etc/asd.conf defining the target directories in the WHATTOSYNC array. These will be syncronized and managed by asd.
WHATTOSYNC=('/var/log' '/srv/http' '/home/foo/bar')
Optionally redefine the location of the tmpfs space to use. Do this in the TMPFS variable. Note that for Arch Linux, the default value of
/dev/shm should work just fine. Be sure to read the warning about using software such as bleachbit with asd since bleachbit likes to remove files stored in
/tmp. This is why a value of
/dev/shm is better.
The initial synchronization will occur when the daemon starts. Additionally, cron (if running) will call it to sync or update once per hour. Finally, asd will sync back a final time when it is called to stop.
Using SysVinit (Arch default)
Call the daemon to start, stop, or sync like any standard Arch daemon:
# rc.d command asd
It is highly recommended to start/stop the daemon at boot/shutdown. This is accomplished by adding asd to the DAEMONS array in
/etc/rc.conf like so:
DAEMONS=(... @asd ...)
Users making use of Systemd may manage the service using the systemctl command. Start/stop the service using:
# systemctl start asd.service # systemctl stop asd.service
Enable the asd daemon to start/stop at boot/shutdown (highly recommended) using:
# systemctl enable asd.service
Sync at More Frequent Intervals (Optional)
Users wishing to have syncs occur more frequently can simply add a line to the root crontab to call the sync function of asd like so:
# crontab -e
Example syncing targets once every ten minutes:
*/10 * * * * rc.d sync asd &> /dev/null
Post in the discussion thread with comments or concerns.