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