Tom Smith wrote: > Currently, I am looking at “CFLAGS= -O”.
You don't mention which gzip version. If you haven't already, please try the current version, gzip 1.8. Its 'configure' script should default to -O2 optimization for GCC, and to no optimization for other compilers. To some extent this is arbitrary. Tweaking this further is up to you. For example, -march=native is better for some usages but not for others, which is why it is not the default.
