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On Tue, 2008-02-19 at 20:07 +0100, b.n. wrote: |
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> Ritesh Kumar ha scritto: |
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> > On Feb 19, 2008 12:09 PM, Florian Philipp <lists@f_philipp.fastmail.net> |
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> > wrote: |
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> > |
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> > |
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> > On Tue, 2008-02-19 at 11:28 +0100, b.n. wrote: |
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> > > Lowe Schmidt ha scritto: |
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> > > > Hi. |
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> > > > |
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> > > > I'm planning on buying myself a MacBook and I'm just wondering |
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> > if anyone |
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> > > > knows how many hours I will get out of it if I run Gentoo. I |
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> > mainly use |
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> > > > a bunch |
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> > > > of terminals, gvim and some lightweigth gtk app so nothing heavy |
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> > going on. |
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> > > > |
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> > > > All input appreciated |
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> > > |
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> > > My Macbook Pro with light, normal usage lasts about three hours (OS X |
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> > > lasts at least one hour more). |
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> > > |
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> > > m. |
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> > |
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> > Have you found any reason for this discrepancy? I'd suspect them to be |
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> > on par with the right tuning. |
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> > |
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> > |
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> > Are you doing any kind of CPU frequency scaling? In the kernel (I use |
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> > gentoo sources) configuration enable |
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> |
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> Yes, I do frequency scaling (the ondemand governor is used when the |
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> laptop is unplugged). I also use laptop-mode for the hd and pommed to |
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> tune screen brightness. |
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> |
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> I think the problems are the wireless and the video drivers. The new |
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> Macbook Pro wireless drivers (I bought my machine in late October 2007, |
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> just when Leopard came out -although, well, I found myself almost never |
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> using it) required SVN version of madwifi (dunno if now the stable |
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> version works, will check when upgrading kernel), and so far attempting |
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> to set power saving on my wireless card fails. |
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> |
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> The Macbook Pro also has a nvidia video card. The nvidia drivers work |
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> quite well (apart from some issues with external dvi resolution), but as |
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> far as I know, on it the "Powermizer" feature is somehow disabled. :( |
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> |
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> I guess both things combined can explain at least a significant quantity |
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> of the power drain. Suggestions are much welcome, I hate the reduced |
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> battery power. |
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> |
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> m. |
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1. Use laptop-mode if you don't do it by now. Really nice even without |
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its delayed disk write feature. |
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2. Displays are by far the biggest energy consumers. Lower its |
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brightness as far as possible. Some laptops even allow you to switch its |
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backlight off - very nice if you are outdoor. |
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3. Use the powersave-governor. If you really need the additional power |
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ondemand offers, try the conservative-governor. It increases the clock |
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rate slower than ondemand and might stop it from jumping too fast too |
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high. |
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4. Try sys-power/powertop. It shows you processes creating a lot up |
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wakeups for the CPU. It also gives you tips on your kernel config. |
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5. Sometimes a BIOS update helps... |
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Hope this helps. |
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