Submodule update is slow for repositories with several submodules

What steps will reproduce the problem?

1. In any repository, which consists of several submodules, select "Submodule Update..." from TortoiseGit's context menu.
2. In the dialog "Submodule Update" select several oder even all path from the multi-selection list.
3. Choose arbitrary options.
4. Click "OK" to perform action.
5. In the dialog "Git Command Progress" watch all of those "git.exe submodule update" commands for the individual submodules to finish.
6. When finished you can read the total time it took in milliseconds. Hence, in my case, submodule update of TortoiseGit's repository took 14 seconds according to the screenshot

What is the expected output? What do you see instead?

On command line, it is sufficient to run a single command "git.exe submodule update", which only requires a fraction of the time to finish. In the same repository this command took only six seconds in my case. I expect TortoiseGit to make efficient use of git's command line to reduce time of submodule update. For the use case of updating only a subset of the submodules, git's command line supports a space separated list of submodules after the trailing --. This call is also significantly faster than calling git multiple times.

What version of TortoiseGit and Git are you using? On what operating system?

• TortoiseGit 2.13.0.1
• git version 2.35.1.windows.2
• Windows 10 Build 19043.1766

Please provide any additional information below.

• n/a