[zfs-discuss] Lower latency ZIL Option?: SSD behind Controller BB Write Cache

James
Thu, 27 Jan 2011 14:57:51 -0000

Chris & Eff,
Thanks for your expertise on this and other posts.  Greatly appreciated.
I''ve just been re-reading some of the great SSD-as-ZIL discussions.

Chris,
Cost:  Our case is a bit non-representative as we have spare P410/512''s
that came with ESXi hosts (USB boot) so I''ve budgetted them at ?0.  I
will be in touch for a quote, I just want to get all my theory straight first on
the options.
Benchmarks:   Good point on graph direction and I look forward to seeing any
further papers.
Latency:   Yes the 9.9ms avg latency (pg 49) was what initially got me thinking
about adding the BBWC in front.    Thanks for reviewing that theory.    Good to
know it''s an option.

Eff,
Thanks for the Vertex review.  Very helpful.     Do you use mirror''d
DDRDrives (or have you so much confidence in them you risk single devices?).