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On Mon, Jul 05, 2010 at 02:17:26PM -0700, Mark Knecht wrote: |
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> On Mon, Jul 5, 2010 at 12:11 PM, Willie Wong <wwong@××××××××××××××.edu> wrote: |
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> > On Mon, Jul 05, 2010 at 09:16:14AM -0700, Mark Knecht wrote: |
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> >> I'm trying to capture the full boot log when booting from the Gentoo |
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> >> install CD but it seems the buffer isn't deep enough to get the whole |
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> >> thing. Is there by chance a command line option that will increase the |
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> >> depth of what's captured by dmesg so that I can get all the way back |
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> >> to the beginning? |
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> > |
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> > pass the following parameter to the kernel on GRUB/LILO: |
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> > |
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> > log_buf_len=n |
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> > |
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> > where n is a power of two. By default it is 16384. You can change it |
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> > to 131072 (= 2^17) to get a much larger kernel log ring buffer. If you |
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> > put in something that is not a power of two, the kernel will ignore |
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> > the option. |
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> > |
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> Thanks for the ideas. I've been trying them but so far no luck. |
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> |
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> In my normal booting kernel (on the system hard drive) I did push |
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> the length up to 18. With that setting dmesg prints all the way back |
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> to the beginning. However booting the Live CD I hit F1, it shows the |
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> kernels, so I type |
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> |
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> gentoo log_buf_len=18 |
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> |
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18 is not a power of two. |
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Why didn't you just try 131072, like I suggested? In maths notation, |
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n = 2^k |
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for some natural number k. 18 fails that miserably. :) |
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Cheers, |
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|
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W |
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-- |
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Willie W. Wong wwong@××××××××××××××.edu |
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Data aequatione quotcunque fluentes quantitae involvente fluxiones invenire |
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et vice versa ~~~ I. Newton |
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