Subject: Re: DEV_B_SIZE
To: None <>
From: Julian Elischer <>
List: tech-kern
Date: 01/31/2003 12:40:28
On Fri, 31 Jan 2003 wrote:

> In message <>, Ju
> lian Elischer writes:
> >
> >
> >One thign I thought of is that it is not uncommon to 'dd' an entire
> >filesystem from one partition to another.
> >If we create a filesystem that is 'aligned' and we copy it to be 
> >'unalligned', we'd have a sudden performance drop for no immediatly
> >obvious reason. What was one write, would become a 2-sector read,
> >modify and 2-sector write. Especially when copying from one failing
> >drive to another with slightly different characteristics.
> If you run dd without bs=ALOT you deserve bad throughput.

I'm talking about the performance of the filesystem after it's been

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