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Message-ID: <D8A848BC8761493EA5A049BFA77852CF@multiplay.co.uk>
From: "Steven Hartland" <killing@multiplay.co.uk>
To: "Borja Marcos" <borjam@sarenet.es>,
 "FreeBSD-scsi" <freebsd-scsi@freebsd.org>
References: <A04E6D4A-907E-45AB-9668-0BF6827FD178@sarenet.es>
Subject: Re: Samsung 840 Pro SSD and quirks
Date: Mon, 1 Sep 2014 16:44:00 +0100
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We saw a noticable performance increase on 4k on our 8TB 840
array but I too couldn't find any concrete information either.

If anyone has this info and can confirm either way that would
be great.

    Regards
    Steve

----- Original Message ----- 
From: "Borja Marcos" <borjam@sarenet.es>


>
> Hi,
>
> I have just noticed that the Samsung 840 SSDs now have the 4 KB block 
> quirk added.
>
> Is this really the case? I've been playing with them some time ago and 
> I didn't notice performance differences between using ZFS on them 
> either
> "directly" (advertised 512 byte blocks) or forcing 4 KB blocks using 
> gnop.
>
> Just surprised, I didn't find references to the true block size.