Recently my builds that use R suddenly increased their runtime from around 3 minutes to over 9 minutes. The increase is entirely due to this command in the setup process of the VM which takes over 6 minutes to run:
tlmgr update --self
Not only does it take forever to run, but it fails. Here are the related log lines:
748No connection to the internet. 749Unable to download the checksum of the remote TeX Live database, 750but found a local copy so using that. 751 752You may want to try specifying an explicit or different CTAN mirror; 753see the information and examples for the -repository option at 754http://tug.org/texlive/doc/install-tl.html 755(or in the output of install-tl --help). 756 757tlmgr: package repository http://ftp.math.purdue.edu/mirrors/ctan.org/systems/texlive/tlnet (not verified: unknown) 758tlmgr: saving backups to /home/travis/texlive/tlpkg/backups 759tlmgr: no self-updates for tlmgr available. 760
It appears to me that the version of Latex is so far out of date that it cannot even update itself any longer. I was able to solve the problem by specifying that Latex not be installed (“latex: false”) in the my build YAML and then manually installing it later in the build.
I believe this is the repo that is being used for the texlive install, and it hasn’t been updated since mid 2016.
Edited to add: One other problem I noticed when trying to debug this is that somehow the mirror used for CTAN is hardcoded to a Purdue mirror that is no longer online. You can see it in line 757 above.