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From: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>
To: Stefan Esser <se@freebsd.org>
Subject: Re: stupid UFS behaviour on random writes
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>
> But I doubt that such a change would improve performance in the

you doubt but i am sure it would improve it a lot. Just imagine multiple 
VM images on filesystem, running windoze with 4kB cluster size, each writing something.

no matter what is written from within VM it ends up as read followed by 
write, unless blocks are already in buffer cache.