Re: /proc/config reducing kernel image size

From: DervishD (lkml_at_dervishd.net)
Date: 09/14/04

  • Next message: Deepak Saxena: "[PATCH] Document ARM pci=firmware option" 
    Date:	Tue, 14 Sep 2004 19:26:46 +0200
To: Tom Fredrik Blenning Klaussen <bfg-kernel@blenning.no>

        Hi Tom :)

     * Tom Fredrik Blenning Klaussen <bfg-kernel@blenning.no> dixit:
    > There is no point in storing all the comments and unused options in the
    > kernel image. This typically reduces the config size to about 1/5th
    > before compressing, and to about 1/4th after compressing.

        I'm with you in that there is no point in storing the comments,
    but I disagree about the unused options. Storing the unused options
    as comments is more useful than it seems ;)

        Look at this example. You want to know if you have 'CONFIG_PNP'
    enabled, so you do something like 'grep CONFIG_PMP /proc/config' (the
    typo PNP->PMP is intended here). Of course that commands doesn't
    print anything due to the typo. If you store the disabled options as
    comments and a grep fails, you probably mispelled the config option,
    or you're referring to a config option not present in your old
    kernel, but if you remove them and you mispell the config option
    there is no (automatic) way of knowing if you made a typo or if the
    option is disabled. Any automatic search can, potentially, give you a
    false negative.

        I'm not really sure about it, but I think that the unset options
    are left as comments for the sake of automation. The space saving
    doesn't (IMHO) worth the pain.

    > I've also added the configuration option of how you want to compress it.

        Compression is always welcome, I suppose ;) Thanks for the idea.

        Raúl Núñez de Arenas Coronado 

    -- 
Linux Registered User 88736
http://www.pleyades.net & http://raul.pleyades.net/
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