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From: Julian Elischer <julian@elischer.org>
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Cc: freebsd-fs@freebsd.org
Subject: Re: 24 TB UFS2 reality check ?
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Juri Mianovich wrote:
> 
> 
> --- On Tue, 7/8/08, Bakul Shah <bakul@bitblocks.com> wrote:
> 
> 
>> I vaguely recall it was more like 700MB of memory per
>> Terabyte on a 50% filled UFS2.  Things may have improved
>> in the three years since I did that.  I don't recall
>> the time
>> to fsck but it was pretty bad!  That was the main reason I
>> switched from UFS2.
> 
> 
> Why does fsck need to reserve all that memory in advance and hold it the entire fsck ?  Is it necessary by definition, or could it be written to not require that ?
> 
> 
>       

it doesn't reserve it .. that's how much data it builds up