Re: [PATCH] udevd: Shrink struct token to 12 bytes

[Alan Jenkins <alan-jenkins@tuffmail.co.uk>]

Kay Sievers wrote:
> On Thu, Nov 6, 2008 at 00:04, Alan Jenkins <alan-jenkins@tuffmail.co.uk> wrote:
>   
>> Kay Sievers wrote:
>>     
>>> On Wed, Nov 5, 2008 at 20:55, Alan Jenkins <alan-jenkins@tuffmail.co.uk>
>>> wrote:
>>>
>>>       
>>>> Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
>>>>
>>>> diff --git a/udev/udev-rules.c b/udev/udev-rules.c
>>>>
>>>>         
>>> I liked the 16 byes, and now we can have only 255 keys per rule. :)
>>>
>>>       
>> Hmm, that wasn't my intention.  rule.token_count is a short so it should be
>> good for 64k.  You'd hit the line buffer limit first.
>>     
>
> Ah, you are right, it's a short. Yeah, even with 255 we would hit the
> line buffer probably. :)
>
>   
>>> I get now with: "shrunk to 81012 bytes tokens (6751 * 12 bytes), 68009
>>> bytes buffer". Maybe we should check the duplicates in the strings and
>>> tail of strings while parsing, we can get rid of another 20kb, I
>>> guess. :)
>>>
>>>       
>> Not sure about the O(n^2) scanning though.  I tried a trie, but it's 100+
>> lines of dense C and needs a hundred K or so during parsing - it just seemed
>> like overkill.  It did shave ~15K off my ~25K string buffer.  I can send it
>> if you like.
>>     
>
> Hmm, maybe it's not worth, and may cost too much at bootup. But if you
> have it working, I would like to see how much it is here. But don't
> bother if it's too much effort, we will probably not apply that.
>   
I had another go and got the index down to ~25K for my installation.  So 
I guess it's worth having a look at.