From mboxrd@z Thu Jan  1 00:00:00 1970
From: John Robinson <john.robinson@anonymous.org.uk>
Subject: Re: md-raid and block sizes
Date: Tue, 28 Dec 2010 11:45:15 +0000
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On 27/12/2010 19:02, Doug Dumitru wrote:
[...]
> The same rules apply to most SSDs.  Most SSDs prefer 4K alignment
> because of how the FTL (Flash Translation Layers) operate, even though
> <4K will sometimes still work pretty well.

If I remember correctly, it may be better to align on SSDs at a larger 
granularity, to the SSDs' erase block size, which may be up to 512K 
depending on the SSD, though I don't remember at all how well Linux 
filesystems, VFS, block layer drivers etc. handle SSD TRIM etc.

Cheers,

John.