From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.7.10) Gecko/20050719 Red Hat/1.0.6-1.4.1 Firefox/1.0.6 Description of problem: The default config file sets the following config options: CONFIG_DEBUG_INFO=y and CONFIG_CC_OPTIMIZE_FOR_SIZE=y this ends up compiling most of the files with -g -Os wouldn't it be preferable for performance to compile with both this options unsetted? Than the code would be compiled with -O2? Version-Release number of selected component (if applicable): kernel-smp-2.6.9-22.EL How reproducible: Always Steps to Reproduce: 1.compile the kernel with make bzImage V=1 2.see that most files are compiled with -g -Os 3. Actual Results: most kernel files are compiled with -g -Os Expected Results: if you unsetted the CONFIG_DEBUG_INFO and the CONFIG_CC_OPTIMIZE_FOR_SIZE then most file will be compile with -O2 Additional info:
debug info is set so that the debugging info can get stripped out to the -debuginfo rpms. -Os is used because cache footprint is more important on modern processors than microoptimisations.