[OpenIndiana-discuss] Three specific N54L microserver related questions. Sort of Re: low low end server...

[Reginald Beardsley]

What is the basis for the "need" for an SSD or USB stick?  Is there any reason to think the additional cost and complexity will improve the performance?  Several people suggested this arrangement when I was deciding on what to do, but in the end I decided the additional complexity wasn't worth the effort and risks.  I particularly didn't like the hacked BIOS some advocated to allow a mirrored root pool using an SSD.

Using a 100 GB partition for a 4 way mirror root pool  and the rest of the disk in a 4 drive RAIDZ2 data pool will give at least 100 MB/s R/W and it can recover from a 2 disk failure without data loss.  At current prices that 100 GB root pool is ~$4 US which is a fraction of the cost of an SSD or  USB.  So it seems to me you'd need a big boost in performance to justify an SSD instead.  It seems unlikely to me that the overall system performance would improve much if at all for a home media server application.  

If the N40L is CPU bound on RAIDZ2 as I believe to be the case, then on the N54L you should get closer to the 179 MB/s i got with RAIDZ1 on the N40L.  This also means that a single spare drive will allow you to start recovery immediately.  With 4 TB drives, it will take a while to recover from a disk failure, so the double failure window begins to be significant.  The simplicity of the recovery process is also appealing.  Insert replacement drive and start recovery.  Would you really want to keep a spare disk and a spare SSD on the shelf?

I don't need the space, but the cost of the N54L is low enough that I'd probably just use multiple servers instead of fiddling with configuring more drives into a machine designed for 4.  An external enclosure and an HBA eats up much of the cost of another N54L.


--------------------------------------------
On Tue, 2/18/14, Hans J. Albertsson <hans.j.albertsson at branneriet.se> wrote:

 Subject: [OpenIndiana-discuss] Three specific N54L microserver related questions. Sort of Re: low low end server...
 To: "Discussion list for OpenIndiana" <openindiana-discuss at openindiana.org>
 Date: Tuesday, February 18, 2014, 5:27 AM
 
 1. Is it really worthwhile to mirror
 an SSD-based ZIL & L2ARC cache, if the SSD has proper
 power loss protection??
     Why: If not I might boot off a USB 3.0 stick
 (Sandisk Extreme Cruzer 16GB???) and use a smaller SSD for
 the caches only.
 
 2. Can the PCIe x4 slot in the N54L be used for anything
 except the Remote Access/IPMI card?
     Why: I'd like to add a 2-4 port Gigabit card
 with server support properties, w/o blocking the x16 slot. I
 can manage the distance to the backplate using short cat 6
 cables to RJ45 sockets on a separate backplate.
 
 3. How do you bring the eSATA port, the sixth SATA port,
 back inside the enclosure in the neatest manner possible??
     Why: To add a 5th Wd Red 3TB disk for a 12TB
 raidz1 setup, sitting in an adapter for the 5.25" space,
 still running an SSD based cache from a proper SATA port,
 also in that same adapter.
 
 
 
 
 
 
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