On Tue, Dec 11, 2012 at 06:36:47PM +0100, Frank Steinmetzger wrote > * I???m interested in the question of -O2 vs. -Os. > Some sources say -Os is bad, b/c it breaks debugging and is mainly > untested. I won???t do heavy developing on it anyway, and Atoms do > have a puny cache. So I wonder whether -Os would improve execution > time and RAM usage noticably. Diskspace itself is not an issue.
I do builds on the netbook. My generic make.conf CFLAGS line is... CFLAGS="-O2 -march=native -mfpmath=sse -fomit-frame-pointer -pipe -fno-unwind-tables -fno-asynchronous-unwind-tables" ...on my machines. "-fno-unwind-tables -fno-asynchronous-unwind-tables" reverses a "new and improved feature" of GCC that bloats the busybox binary (and presumably other binaries) 15% to 20%. See the short thread http://lists.busybox.net/pipermail/busybox/2012-September/078326.html for background. The busybox developers obviously want to reduce every bit of disk and/or ram usage, because busybox is used in a lot of ram and disk constrained embedded systems. I don't know if it's possible to easily add another gig of ram. It would certainly help. I have an ancient netbook. It has 2 gigs of ram, but is restricted to 32-bit only. BTW, does the netbook jave a Poulsbo GPU? There are some hints at the Arch wiki https://wiki.archlinux.org/index.php/Poulsbo for getting it to work better. I can get HD Youtube videos to play in the "large player", but my machine has 2 gigs of ram. If it's a relatively new Gentoo install, I recommend... emerge system && emerge world ...to get the most optimization. Also, build the "ondemand" cpu governor and enable it (emerge cpufrequtils). This will enable the higher CPU speeds. I think my machine was originally stuck at its lowest CPU frequency due to the "powersave" governor, even with the machine plugged into the wall for power. -- Walter Dnes <waltd...@waltdnes.org> I don't run "desktop environments"; I run useful applications
