Profile-sync-daemon

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Benefits of psd

Running this daemon is beneficial for two reasons:

  1. Reduced wear to physical discs
  2. Speed

Since the profile(s), browser cache*, etc. are relocated into tmpfs (RAM disk), the corresponding onslaught of I/O associated with using the browser is also redirected from the physical disc to RAM, thus reducing wear to the physical disc and also greatly improving browser speed and responsiveness. For example, 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.

Note: Chromium actually keeps its cache directory separately from its browser profile directory. It is not within the scope of profile-sync-daemon to modify this behavior; users are encouraged to refer to the Chromium_Tips_and_Tweaks#Cache_in_tmpfs section of the main Chromium_Tips_and_Tweaks article for several work-arounds.

Supported browsers

Currently, the following browsers are auto-detected and managed:

Setup and installation

profile-sync-daemonAUR is available for download from the AUR. Build it and install like any other package.

Edit /etc/psd.conf

Edit the included /etc/psd.conf defining which user(s) will have their profiles managed by psd.

Example:

# List users separated by spaces whose browser(s) profile(s) will get symlinked 
# and sync'ed to tmpfs.
# Do NOT list a user twice!
USERS="facade happy"
Note: At least one user must be defined.

Optionally uncomment the BROWSERS array and populate it with whichever browser(s) are to be sync'ed to tmpfs. If the BROWSERS array stays commented (default) then all supported browser profiles will be sync'ed if they exist.

Example: Let's say that Chromium, Opera and Midori are installed but only Chromium and Opera are to be sync'ed to tmpfs since the user keeps Midori as a backup browser and it is seldom used:

# List browsers separated by spaces to include in the sync. Useful if you do not
# wish to have all possible browser profiles sync'ed.
#
# Possible values:
#   chromium
#   conkeror.mozdev.org
#   firefox
#   firefox-trunk
#   google-chrome
#   heftig-aurora 
#   midori
#   opera
#   opera-next
#   qupzilla
#
# If the following is commented out (default), then all available/supported 
# browsers will be sync'ed, separated by comma
BROWSERS="chromium opera"

Using psd

Preview mode (parse)

The 'parse' option can be called to show users exactly what psd will do based on the /etc/psd.conf entered. Call it like so:

$ profile-sync-daemon parse
 Profile-sync-daemon v5.24

psd will manage the following per /etc/psd.conf settings:

browser/psname:  chromium/chromium
owner/group:     facade/users
sync target:     /home/facade/.config/chromium
tmpfs dir:       /tmp/facade-chromium
profile size:    81M

browser/psname:  firefox/firefox
owner/group:     facade/users
sync target:     /mnt/data/docs/facade/mozilla/firefox/1Zp9V43q.banking
tmpfs dir:       /tmp/facade-firefox-1Zp9V43q.banking
profile size:    5.9M

browser/psname:  firefox/firefox
owner/group:     facade/users
sync target:     /mnt/data/docs/facade/mozilla/firefox/obg67zqQ.proxy
tmpfs dir:       /tmp/facade-firefox-obg67zqQ.proxy
profile size:    17M

As shown in the output and as stated above, if no specific browser or subset of browsers are defined in the BROWSERS array, psd will sync ALL supported profiles that it finds for the given user(s).

Running psd to manage profiles

Do not call /usr/bin/profile-sync-daemon to sync or to unsync directly. Instead use the provided service files.

Both a systemd service file and a timer are provided and should be used to interact with psd. Both should be invoked together! The role of the timer is update the tmpfs copy/copies back to the disk which it does once per hour. Failure to start the resync timer will result in the profile being sync'ed only on start up and shutdown.

Start psd and psd-resync service and enable them to start/stop at boot/shutdown (highly recommended).

Obviously, you must first close your browser before starting the service.

Sync at more frequent intervals (optional)

The package provided timer syncs once per hour. Users may optionally redefine this behavior simply by extending the systemd unit. The example below changes the timer to sync once every ten minutes:

/etc/systemd/system/psd-resync.timer.d/frequency.conf
[Unit]
Description=Timer for Profile-sync-daemon - 10min

[Timer]
# Empty value resets the list of timers
OnUnitActiveSec=
OnUnitActiveSec=10min

See man systemd.timer for additional options.

Caveats for Firefox and Heftig's Aurora ONLY

The way psd keeps track of browser profiles and sync targets requires users to have a unique name as the last directory for all profiles in their respective $HOME/.mozilla/browser/profiles.ini files. psd will check when it is called to run for this and refuse if this rule is not satisfied. The following is an example of a BAD profile that will fail the the test. Note that although each full path is unique, they both end in the same name! Again, the user must modify the profiles.ini and the corresponding directory on the filesystem to correct this in order to use psd.

~/.mozilla/firefox/profiles.ini
[General]
StartWithLastProfile=1

[Profile0 for user facade]
Name=normal
IsRelative=0
Path=/mnt/data/docs/facade/mozilla/firefox/myprofile.abc
Default=1

[Profile1 for user happy]
Name=proxy
IsRelative=0
Path=/mnt/data/docs/happy/mozilla/firefox/myprofile.abc

FAQ

Note: The first three questions apply to versions of psd equal to or greater than v5.40 only.

Q1. My system crashed and didn't sync back. What do I do?

Odds are the "last good" backup of your browser profiles is just fine still sitting happily on your filesystem. Upon restarting psd (on a reboot for example), a check is preformed to see if the symlink to the tmpfs copy of your profile is invalid. If it is invalid, psd will snapshot the "last good" backup before it rotates it back into place. This is more for a sanity check that psd did no harm and that any data loss was a function of something else.

Q2. Where can I find this snapshot?

It depends on the browser. You will find the snapshot in the same directory as the browser profile and it will contain a date-time-stamp that corresponds to the time at which the recovery took place. For example, chromium will be ~/.config/chromium-backup-crashrecovery-20130912_153310 -- of course, the date_time suffix will be different for you.

Q3. How can I restore the snapshot?

  • Stop psd.
  • Confirm that there is no symlink to the tmpfs browser profile directory. If there is, psd did not stop correctly for other reasons.
  • Move the "bad" copy of the profile to a backup (don't blindly delete anything).
  • Copy the snapshot directory to the name that browser expects.

Example using Chromium:

mv ~/.config/chromium ~/.config/chromium-bad
cp -a ~/.config/chromium-backup-crashrecovery-20130912_153310 ~/.config/chromium

At this point you can launch chromium which will use the backup snapshot you just copied into place. If all is well, close the browser and restart psd and psd-resync (if using systemd). You may safely delete ~/.config/chromium-backup-crashrecovery-20130912_153310 at this point.

Support

Post in the discussion thread with comments or concerns.

PSD on other distros

psd is a bash script and should therefore run on any Linux distro. Below is a list of distros known to package psd, and a link to download their respective packages.

Note: Different distros use different init systems. The packages linked below are configured to use the default init system for the given distro.
Distro Default Init System Link to Package
Arch Systemd AUR.
Chakra Systemd CCR.
Debian Upstart Graysky's PPA. See instruction below.
Exherbo Systemd In official repos.
Fedora Systemd In official repos.
Gentoo OpenRC In official repos.
Mint Upstart Graysky's PPA. See instruction below.
OpenSUSE Upstart Packaged by Overman79.
Ubuntu Upstart Graysky's PPA, See instruction below.
Void Systemd In official repos.

Debian

To add the PPA (personal package archive) to your Debian (tested on Squeeze) system, and to install psd:

# echo "deb http://ppa.launchpad.net/graysky/utils/ubuntu quantal main" > /etc/apt/sources.list.d/graysky.list
# echo "deb-src http://ppa.launchpad.net/graysky/utils/ubuntu quantal main" >> /etc/apt/sources.list.d/graysky.list
# apt-key adv --keyserver keyserver.ubuntu.com --recv-keys FF7F9516
# apt-get update
# apt-get install profile-sync-daemon

Mint and Ubuntu

To add the PPA (personal package archive) to your Ubuntu (packages available for Lucid and newer) system, and to install psd:

$ sudo add-apt-repository ppa:graysky/utils
$ sudo apt-get update
$ sudo apt-get install profile-sync-daemon

See also