How do I speed up new Terminal tab loading time?

Question

How can i speed up the terminal startup in Lion?

I'm not referring to the startup of the Terminal application, but to the startup terminal windows, like when i open a new tab.

I don't have anything in my .bash_profile file and i run rm -rf /private/var/log/asl/*.asl every 4 hours (which clear those files that usually make terminal slow ).

Currently, when i open a new tab, it takes 3-4 seconds until i can run something.

Answer 1

Create an empty file in your home folder called .hushlogin; this will significantly decrease the time it takes for a Terminal.app tab to appear.

When you create a new Terminal tab, you are going through the login process. The process involves fetching various information about your previous login session, message of the day, and displaying system messages. This can be the source of significant delays. Try hushing these messages to see if the delay disappears.

You can create the .hushlogin file in Terminal.app using the following command:

touch ~/.hushlogin

The file will take effect immediately.

You can learn more about the .hushlogin file and the login process in general in the login manual.

Answer 2

Short Answer:

• Open Terminal Preferences
• Select the Startup tab
• Select "Shells open with: Command", and use "/usr/bin/bash" as the command.

Important: Do not use "/bin/bash" as the startup command. If "/usr/bin/bash" does not exist on your system, create a symbol link: sudo ln -s /bin/bash /usr/bin/bash

To verify the fix:

• Open a new Terminal windows.
• "Last Login:" should not be displayed
• Open the inspector (Command + I) and select the Info tab.
• The command should read login -pfq username /usr/bin/bash

Important: If the login command does not include the -q parameter, then you have not fixed the problem.

Details:

Terminal uses /usr/bin/login to launch each new window/shell. By default, /usr/bin/login will display the date of your last login. To get this last login date, it searches the ASL (Apple System Log) database at /var/log/asl/. These log files can be very heavily fragmented and it's this file fragmentation that causes the delay when opening a new window or tab.

To see this in action, run sudo opensnoop | grep login in a Terminal window, then open a new Terminal window.

To prevent /usr/bin/login from doing this ASL search, you must pass the -q parameter. The only way Terminal will pass the -q parameter is when you specify a custom shell command in the Preferences.

Note: .hushlogin does not prevent /usr/bin/login from doing the ASL search. This can be confirmed by using the opensnoop command above.

Answer 3

Reduce your history to something between 4 and 10 thousand lines and perhaps try quitting and discarding all saved windows. I have seen both make a difference on slower machines - especially ones without SSD for storage.

Answer 4

It is all about investigating the cause. You can see what's being done while the process starts by inputing bash -x which will print out the process of starting up the shell.

Personally, I only notice the delay between activation and de-activation of the app and in the first tab created after a period of activity. It always makes me think that it is about memory pages being moved around.