This article is from the Frequently Asked Questions for Linux, the Free/Open Source UNIX-like operating system kernel that runs on many modern computer systems. Maintained by David C. Merrill with numerous contributions by others. (v1.0).
A: In Linux 1.3.57 and later, the format of /proc/meminfo was changed in a way that the implementation of free doesn't understand.
Get the latest version, from metalab.unc.edu, in /pub/Linux/system/Status/ps/ procps-0.99.tgz.