On 10/14/2011 5:49 AM, Darren J Moffat wrote:
On 10/14/11 13:39, Jim Klimov wrote:
Hello, I was asked if the CF port in Thumpers can be accessed by the OS?
In particular, would it be a good idea to use a modern 600x CF card
(some reliable one intended for professional photography) as an L2ARC
device using this port?
I don't know about the Thumpers internal CF slot.
I can say I have tried using a fast (at the time, this was about 3
years ago) CF card via a CF to IDE adaptor before and it turned out to
be a really bad idea because the spinning rust disk (which was SATA)
was actually faster to access. Same went for USB to CF adaptors at
the time too.
Last I'd checked, the CF port was fully functional.
However, I'd not use it as L2ARC (and, certainly not ZIL). CF is not
good in terms of either random write or read - professional-grade CF
cards are optimized for STREAMING write - that is, the ability to write
a big-ass JPG or BMP or TIFF as quickly as possible. The CF controller
isn't good on lots of little read/write ops.
In Casper's case, the CF->IDE adapter makes this even worse, since IDE
is spectacularly bad at IOPS.
I can't remember - does the X4500 have any extra SATA ports free on the
motherboard? And, does it have any extra HD power connectors?
http://www.amazon.com/dp/B002MWDRD6/ref=asc_df_B002MWDRD61280186?smid=A2YLYLTN75J8LR&tag=shopzilla_mp_1382-20&linkCode=asn&creative=395105&creativeASIN=B002MWDRD6
Is a great way to add a 2.5" drive slot, but it's just a physical slot
adapter - you need to attach a standard SATA cable and HD power
connector to it.
If that's not an option, find yourself a cheap PCI-E adapter with eSATA
ports on it, then use an external HD enclosure with eSATA for a small SSD.
As a last resort, remove one of the 3.5" SATA drives, and put in an SSD
in a 2.5"->3.5" converter enclosure.
Remember, you can generally get by fine with a lower-end SSD as L2ARC,
so a 60GB SSD should be $100 or less.
-Erik
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