Re: Current Grub2 & problem with /boot on different drive

[Dean Loros <ubuntu1user@gmail.com>]

Greetings--

Well Vladimir, the modification to grub.cfg makes a 20sec
difference--times went from 3 min 50 sec to 3 min 30 sec--better, but
still a "bit" long :)  So I would say that option #3 has very little
effect & I really do not want to hardcode as per option #2....I am open
to "interesting" mods to bring the time down to "normal" levels & It
looks like Colin is willing to do some package building in between his
busy workweek. So what are your thoughts as how this can be approached?


Date: Mon, 21 Sep 2009 15:58:17 +0100 From: Colin Watson
<cjwatson@ubuntu.com> Subject: Re: Current Grub2 & problem with /boot on
different drive To: The development of GRUB 2 <grub-devel@gnu.org>
Message-ID: <20090921145817.GM13423@riva.ucam.org> Content-Type:
text/plain; charset=us-ascii On Mon, Sep 21, 2009 at 04:22:53PM +0200,
Vladimir 'phcoder' Serbinenko wrote:

> > Colin Watson wrote:
>   
>> > > On Sun, Sep 20, 2009 at 10:00:13PM +0200, Vladimir 'phcoder' Serbinenko wrote:
>>     
>>> > >> As a workaround for time being you can use one or more of the following:
>>> > >> 1) Increase cache size. Can this be done in 1.97?
>>> > >> Change include/grub/disk.h and replace
>>> > >> #define GRUB_DISK_CACHE_NUM     1021
>>> > >> with a bigger number
>>>       
>> > >
>> > > I'm a little baffled. Why does the disk cache size make a difference
>> > > here? He has four disks - I'd have thought that 1021 would be plenty.
>>     
> > 
> > 1021 is the number of cached 4KiB blocks and is used in hash
> > calculations. If he has a lot of cache misses it will result in long
> > boot times
>   
Do you have a recommendation for a new value? I can build a test package
and ask Dean to try it out.


-- 
Dean Loros
autocrosser at ubuntuforums.org
Performance by Design Ltd.