From owner-freebsd-fs@freebsd.org  Wed Aug 19 16:14:27 2015
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Date: Wed, 19 Aug 2015 11:14:24 -0500 (CDT)
From: Bob Friesenhahn <bfriesen@simple.dallas.tx.us>
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To: PK1048 <paul@pk1048.com>
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Subject: Re: Optimizing performance with SLOG/L2ARC
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On Wed, 19 Aug 2015, PK1048 wrote:
>
> I have seen the RAM based battery-backed-up drives, and some are not 
> even ludicrous in terms of price, but I did not see any with FreeBSD 
> driver support. Since they are generally PCIe based (for speed), 
> drives are needed.

RAID-oriented HBAs often offer battery-backed SRAM support.  One would 
think that using one of these with a single attached SSD should serve 
as a lower-latency zil than the SSD itself.  Driver support is then 
readily available.

Bob
-- 
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/