did gbde on swap destroy some boot sectors?

Eugene eugene3 at web.de
Thu Jul 29 17:36:38 PDT 2004


Scot Hetzel wrote:

>>my swap labels are the following ones...
>>
>>/dev/da0s1b
>>/dev/da1s1b
>>/dev/da2s1b
>>
> 
> What we should be looking at are the disklabels for those devices:
> 
>    disklabel /dev/da0s1
> 
> As the swap partition could be overlapping with your root partition. 
> Then when your system crashed, the system wrote to the end of your
> swap partition, which wrote over your root partition.

i configured the labels some moths ago from within sysinstall when i 
installed freebsd, they realy shouldnt overlap. im heavily using my 
swap, so it should have crashed earlier that root label...

> 
> 
>>and they are located at the very beginning of all hard drives for speed
>>reasons...
>>
> 
> Actually, you want your swap partition as close to the center of the
> hard drive as possible to minimize the movement of the drive heads,
> thus increasing the speed.
> 
> Scot

seems i was too fixated onto continouously read/write speed alone being 
faster at the beginning ignoring the reposition of the heads from label 
to label... but i still guess there is a chance the kernel does wait and 
read/write in chunks, minimizing head-reposition over long distances, 
doesnt it? there are even tunables about swap... hi_swap and so on wich 
are realy of use...

should i benchmark where to locate and how to size it or will i only 
gain performance far from being noticeable?

Eugene



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