I have a repo from which pull takes forever because the server has little free RAM and it is swapping a lot while
remote: Compressing objects: 24%
From the git documentation:
core.bigFileThreshold Files larger than this size are stored deflated, without attempting delta compression. Storing large files without delta compression avoids excessive memory usage, at the slight expense of increased disk usage. Default is 512 MiB on all platforms. This should be reasonable for most projects as source code and other text files can still be delta compressed, but larger binary media files won't be. Common unit suffixes of 'k', 'm', or 'g' are supported.
So I guess by setting this value to something like 1 would do the trick.
Extended by comments: you can set this with a git config --add core.bigFileThreshold 1
command. It works for bare repos as well.