on my Debian system where many packages are installed, the /var/lib/dpkg/info/ directory is quite big:
$ ls -l /var/lib/dpkg/info/ |wc
58183 523640 3812873
It is also very fragmented:
$ filefrag /var/lib/dpkg/info/
/var/lib/dpkg/info/: 222 extents found
So I tried to defrag it with e4defrag. Unfortunately I could only defrag files inside /var/lib/dpkg/info/ and /var/lib/dpkg/, but not /var/lib/dpkg/info itself.