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Date: Fri, 3 Oct 2014 05:59:48 -0600 (MDT)
From: Warren Block <wblock@wonkity.com>
To: javocado <javocado@gmail.com>
Subject: Re: Mirrored SSDs for ZIL/SLOG - safety, flushing, capacitors
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On Thu, 2 Oct 2014, javocado wrote:

> I'm setting up a SLOG to improve performance on my ZFS-based fileserver. I
> plan to use 2 mirrored SSD's to create the log device. Before I continue,
> I have some specific questions how to approach which hardware to use.
>
> Primarily, I'm concerned with what damage/corruption may occur when there's
> a power loss.

Do you have a good UPS?

> 2. should I only use SSDs with capacitors? does anyone recommend any? I'm
> seeing good things about the Intel s3500

I think the Crucial M550 SSDs have additional backup capacitors also. 
However, I'm still skeptical about the value of a small SSD power backup 
versus a true UPS for the entire system.