How can I make auto-hide/show for the dock faster?

Solution 1:

To make the Dock instantly leap back into view when it’s needed, rather than slide, open a Terminal window and type the following:

defaults write com.apple.dock autohide-time-modifier -int 0;killall Dock

I find this useful, but if you’d like the animation for the dock to reappear to last for a split-second, try the following:

defaults write com.apple.dock autohide-time-modifier -float 0.15;killall Dock

To explain, changing "0.15" with any number can let you tailor things as it represents the time in seconds taken for the dock to reappear fully.

To revert back to the default sliding effect, open a Terminal window and type the following:

defaults delete com.apple.dock autohide-time-modifier;killall Dock

You can manually set the time it takes for the dock to appear.

_{Unlike the autohide-time-modifier tip posted by Marius Butuc, this command does not remove the animation of the Dock when it appears.}

First, activate auto-hide in System Preferences → Dock → Autohide or type ⌘+⌥+D Then open the Terminal and type:

defaults write com.apple.dock autohide-delay -float 0; killall Dock

0 is the time it takes for the Dock to appear in seconds. You can choose floats and integers e.g. 2, 0.5,...
killall Dock causes the Dock to restart.

Restore the default behavior using...

defaults delete com.apple.dock autohide-delay; killall Dock

Note that com.apple.dock is case sensitive.

According to MacOSHints this trick was found by reverse engineering from the developer Christian Baumgart of Hyperdock.

This command only works in OS X 10.7 or newer.