rospack is too slow

Sometimes old defunct packages - "zombies" - that have had their manifests moved removed or deleted may be making it time-consuming to crawl the directory structure.

Solution: Try running

$ rospack profile

This will tell you the time required to crawl your directory structure and will describe your directory structure, including any zombies that may be in the structure. These will be indicated with an asterisk.

Getting rid of the zombies may improve your system performance - running the command

rospack profile --zombie-only

will list these zombies. From this point you can either manually remove the zombies, or, if it looks to you like the entire list can be safely deleted, you can run the command (be very careful!):

rospack profile --zombie-only | xargs rm -r

This will remove all of the zombie directories, and can potentially may it quicker to navigate or build your ros directory structure.

rospack is unable to find packages that are added recently

The same command as "rospack too slow" section forces full crawl of package directories and might work for addressing this issue.

rospack profile

After running the above, try again rospack find or any command failed.