I found this, thought I'd make an organized thread for it. Enjoy. Feel free to add any contributions.
Source:
Martin's Weekend Coding
Credit:
Martin's Weekend Coding
DISCLAIMER: Apply tweaks at your own risk and be sure to backup any critical data before proceeding with any tweaks. I (Orlandoech) or MacRumors.com are not responsible for any data loss, corruption or hardware failure of any sort.
CONTENTS
- Use Trim Enabler [3rd Party SSD's only]
- Turn off local Time Machine snapshots [laptops only]
- Turn off hibernation [laptops only]
- Set noatime flag
- Move user home directories to HDD [SSD+HDD only]
- Use RAM disk or HDD for temporary files
- Turn off sudden motion sensor [SSD+HDD only]
- Turn off hard drive sleep [SSD+HDD only]
- Misc Tweaks
- Benchmark Tools/Utilities
- References
1. Use Trim Enabler [3rd Party SSD's only]
NOTE: This IS NOT NEEDED for any OEM Apple SSDs in any iMac, Mac Mini, MacBook Pro Retina, MacBook Pro, MacBook Air.
TRIM support is essential for keeping the SSD healthy. Unfortunately, MacOS supports TRIM only for Apple-supplied SSDs. If you bought a 3rd party one like I did, you have to tweak the system to be able to turn on the TRIM support. Trim Enabler is a simple utility that does this for you.
Download TrimEnabler.
2. Turn off local Time Machine snapshots [laptops only]
If you are using the SSD in a laptop, and you turned the Time Machine backups on, you should know that OS X Lion does local snapshots at times when your Time Machine disk is not available. This is quite common you are typically connecting your external TM disk only once in a while or you are using Time Capsule at home but take your laptop to the office every day for 8+ hours. You can confirm if the local TM backups are on by opening Time Machine Preferences:
Image
There is no GUI switch to turn these local backups off, but it can easily be done on the command line. Just start Terminal.app and execute the following command:
Once you do this, the TM Preferences panel will immediately reflect it the text will change from Time Machine keeps local snapshots as space permits, and: to Time Machine keeps:. To turn it back on, you can simply run the following in the Terminal:
Also note, this feature gets turned on automatically whenever you turn off and on the Time Machine so dont forget to turn the local backups back off again whenever you do that.
I found out about how to turn off the local backups from this article:
http://osxdaily.com/2011/09/28/disable-time-machine-local-backups-in-mac-os-x-lion/
Another feature of Mac OS turned on by default on laptops is, that it saves all the memory to disk when entering sleep mode. This is to ensure your laptop does not lose your work if it runs out of battery while sleeping. The more RAM you have, the more gigabytes it writes to the disk every time you close the lid/put it to sleep. I typically do this at least twice a day when leaving the office and when going to sleep in the evening. If you are in a similar situation and you have 8GB of RAM, that means your MacBook writes 16 to 24 GB of hibernation data to your SSD every day. Here is how you can turn this off it will not only make your SSDs life longer, but also significantly speed up the time it takes for your laptop to enter the sleep mode:
Code:
sudo pmset -a hibernatemode 0
I found it in this article:
http://news.metaparadigma.de/osx86-enable-and-disable-hibernation-57/. Reading the man pages for pmset sheds some more light on the factory defaults and meaning of the hibernatemode values:
We do not recommend modifying hibernation settings. Any changes you make are not supported. If you choose to do so anyway, we recommend using one of these three settings. For your sake and mine, please dont use anything other 0, 3, or 25.
Code:
hibernatemode = 0 (binary 0000) by default on supported desktops. The system will not back memory up to persistent storage. The system must wake from the contents of memory; the system will lose context on power loss. This is, historically, plain old sleep.
hibernatemode = 3 (binary 0011) by default on supported portables. The system will store a copy of memory to persistent storage (the disk), and will power memory during sleep. The system will wake from memory, unless a power loss forces it to restore from disk image.
hibernatemode = 25 (binary 0001 1001) is only settable via pmset. The system will store a copy of memory to persistent storage (the disk), and will remove power to memory. The system will restore from disk image. If you want hibernation slower sleeps, slower wakes, and better battery life, you should use this setting.
Once you turn off hibernation, you can also remove the sleep image file that will free up several GB of disk space (depending on how much RAM you have):
Code:
sudo rm /var/vm/sleepimage
MacOS (like other unix-based systems) by default records last access time for every file. I.e. every time you read a file, a write is made on the filesystem to record this action. There is no point in doing it and no side effects if you disable that by mounting the root filesystem with noatime flag set. To do that create a file named for example com.nullvision.noatime.plist (you can pick any other name you wish) in the directory /Library/LaunchDaemons with the following content:
Code:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN"
"http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Label</key>
<string>com.nullvision.noatime</string>
<key>ProgramArguments</key>
<array>
<string>mount</string>
<string>-vuwo</string>
<string>noatime</string>
<string>/</string>
</array>
<key>RunAtLoad</key>
<true/>
</dict>
</plist>
And execute the following command in Terminal:
Code:
sudo chown root:wheel /Library/LaunchDaemons/com.nullvision.noatime.plist
Restart the machine.
You can verify that it worked by executing the following in Terminal:
You should get the following output (i.e. see noatime in the list in parentheses):
Code:
/dev/disk0s2 on / (hfs, local, journaled, noatime)
This tweak was taken from blogs.nullvision.com, which seems to not be available anymore, but I found a mirror of the old content here:
http://www.icyte.com/saved/blogs.nullvision.com/441781
And the same trick (inspired by the same blog) is here:
http://blog.philippklaus.de/2011/04/ssd-optimizations-on-mac-os-x/
This tweak is only useful if you have both SSD as well as HDD in your Mac. Im using this in my iMac. I moved all the content of /Users folder to the HDD and created a symbolic link from the SSD to it (so that I dont have to change the home folder location in the user settings, as I read some applications dont like it and may not work correctly). To do that execute the following commands in Terminal:
Code:
sudo ditto /Users /Volumes/your_hdd_name/Users
sudo mv /Users /Users.bak
sudo ln -s /Volumes/your_hdd_name/Users /Users
UPDATE: To be safe, you should also go to System Preferences, click on Users & Groups, click the lock icon to unlock advanced editing (password prompt will appear). Once unlocked, you should be able to right-click on each user account and choose Advanced Options from the pop-up menu. Once in the Advanced Options dialog, change the Home directory of the user from /Users/user-name to the new location (e.g. /Volumes/HDD/Users/user-name).
Now, check if your home folders are showing up correctly in Finder. If so, restart your computer.
Finally, delete the back-up of your Users folder on the SSD by typing the following into the Terminal:
If you have enough RAM, you can dedicate (typically around 256 to 512 MB) of RAM to a RAM disk. RAM disk is a virtual disk that only resides in memory, so is suitable for storing data that need to live only until you shut down your computer. Temporary files are ideal for this. You can create a RAM disk during the boot time and redirect all the temporary files there. To do that, create a file named MoveTempFoldersToRamDisk.sh in your home directory and put the following content in:
Code:
#!/bin/bash
# +----------------------------------------------------------------------+
# | |
# | Set up Mac OS X to store temporary files in RAM rather than on disk.|
# | |
# | By Philipp Klaus <http://blog.philippklaus.de> |
# | |
# | Originally by Ricardo Gameiro <http://blogs.nullvision.com/?p=357> |
# | Changes by Daniel Jenkins |
# | <http://blogs.nullvision.com/?p=357#comment-1140> |
# | |
# +----------------------------------------------------------------------+
cd /System/Library/StartupItems
sudo mkdir RamFS
sudo chown -R root:wheel RamFS
sudo chmod -R u+rwX,g+rX,o+rX RamFS
cat << "EOF" | sudo tee RamFS/RamFS > /dev/null
#!/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"
EOF
sudo chmod u+x,g+x,o+x RamFS/RamFS
cat << EOF | sudo tee RamFS/StartupParameters.plist > /dev/null
<?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>
EOF
Now, run the following in the Terminal:
Code:
chmod 755 ~/MoveTempFoldersToRamDisk.sh
~/MoveTempFoldersToRamDisk.sh
This creates two RAM disks on startup one 256MB large for /private/tmp (command RAMDisk /private/tmp 256″ in the middle of the above script) and another one 64MB large for /var/run. You can now delete ~/MoveTempFoldersToRamDisk.sh from your computer.
For the changes to take effect, you have to restart.
If you decide to undo this tweak in the future, you can do it simply by deleting /System/Library/StartupItems/RamFS directory from your Mac. E.g. by executing the following command in the Terminal:
Code:
sudo rm -rf /System/Library/StartupItems/RamFS
Again, restart is needed for this to take effect.
There are some small drawbacks to applying this tweak:
- After applying it it takes a few seconds (2-3 on my machine) to shut down
- It lowers the size of RAM usable for applications
If you are bothered by the above and have HDD in your Mac as well, you can consider moving the temporary files to HDD instead of the RAM disk. The steps are similar to moving the user home directories. E.g. to move /private/tmp, execute the following in the Terminal:
Code:
sudo ditto /private/tmp /Volumes/your_hdd_name/private/tmp
sudo rm -rf /private/tmp
sudo ln -s /Volumes/your_hdd_name/private/tmp /private/tmp
RAM disk portion of this tweak taken from here:
http://blog.philippklaus.de/2011/04/ssd-optimizations-on-mac-os-x/
Originally suggested by blogs.nullvision.com (mirror at
http://www.icyte.com/saved/blogs.nullvision.com/441781)
If SSD is the only drive in your Mac, there is no point in using the Sudden Motion Sensor. You can switch it off by executing the following in the Terminal:
Some websites mention SSD may freeze when the hard drive sleep feature is on, so it is recommended to turn it off. However, you probably dont want to do this if you also have a HDD in your Mac. To switch the hard drive sleep off, go to System Preferences->Energy Saver and uncheck Put the hard disk(s) to sleep when possible.
Image
Taken from
http://poller.se/2010/08/optimizing-mac-os-x-for-ssd-drives/
Disable waking up when LID opens
No hibernate
Code:
sudo pmset -a hibernatemode 0
Disabling Sudden Motion Sensor
Verify applied tweaks
Screen capture save format
Code:
defaults write com.apple.screencapture type jpg
Screen capture save location
Code:
defaults write com.apple.screencapture location [path]
Mac login window display System Time
Code:
sudo defaults write /Library/Preferences/com.apple.loginwindow AdminHostInfo Time
Safari single window mode
Code:
defaults write com.apple.Safari TargetedClicksCreateTabs -bool true
Add a Recent files stack to Dock
Code:
defaults write com.apple.dock persistent-others -array-add '{ "tile-data" = { "list-type" = 1; }; "tile-type" = "recents-tile"; }'
Make Dock app icons spring-loaded
Code:
defaults write com.apple.dock enable-spring-load-actions-on-all-items -boolean YES
Snow Leopard Stack Highlight
Code:
defaults write com.apple.dock mouse-over-hilite-stack -boolean YES
Reload Dock
10. Benchmark Tools/Utilities
11. References
The tweaks that I presented are the tweaks that I thought are worth applying. None of them really limits any features. There are other tweaks, which I did not want to apply as I would be giving up on some functionality (such as disabling the Spotlight) or I was not comfortable with (e.g. disabling the swap files). You can find these and more on the following web sites:
