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Message-ID: <503602B8.3050507@wonkology.org>
Date: Thu, 23 Aug 2012 12:15:20 +0200
From: Alex Schuster <wonko@wonkology.org>
Organization: Wonkology
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Subject: Re: [gentoo-user] SSD performance tweaking
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Mark Knecht writes:

>     I'm currently just using a single large partition & ext3. I didn't
> do anything special in fdisk so the partition might not be aligned as
> best it could be. I don't know.

See if the partition's starting block is 63 as it used to be in the 
past. In this case the alignment is wrong, as SSDs have 4K (or even 8K) 
sectors consisting of 8 (or 16) 512 byte blocks. The starting block 
should be divisible by 8 (or 16) because of the large sector size, if 
not, a file system sector spans over two drive sectors, and both heed to 
be accessed when reading a file system sector.

The size of an erasable block of SSDs is even larger, usually 512K, it 
would be best to align to that, too. A partition offset of 512K or 1M 
would avoid this.

	Wonko