[Pc_Support] Off Computer Storage -- Near-line storage ...

[Bryan J. Smith]

On Sun, 2006-06-11 at 21:36 -0500, David Simmons wrote:
> The line of progression:
> create machine -> do video work -> need more space -> add hard drives ->
> machine too hot -> add fans -> livable, but loud -> now need more space
> Guys....I've come to the point where I realize that I'd like to set up a
> NAS type system for a few boxes to share space/files (probably not
> concurrently).  Environments will be mixed - Windows/Linux clients.

I hope you saw my article "Dissecting Virtual Tape Libraries" last fall:
http://www.samag.com/documents/sam0509a/  

It dissects how near-line disk is a very capable solution for backups
(including augmenting off-line tape), which also applies to near-line
storage in general.

> Thanks to Bryan, I'm familiar with the need to use some of the newer bus
> structures to really gain Gigabit network speeds - BUT, can you attain
> almost local speed with hard-drives?

Yes!  Especially if you use a dedicated GbE "out-of-band/storage"
network with 9000 byte jumbo frames (to avoid having to setup VLANs and
buy more expensive switches).

> What about if using SATA-II drive in host machine?

Makes *0* difference from SATA/150 or ATA/133.  Most drives can't
surpass a 75MiBps sustained DTR.

In actuality, all most SATA2/300 drives mean is that they have a native
SATA interface.  Most SATA/150 drives are using SATA/150 to ATA/133
adapters internally, including directly on the PCB of the hard drive.

Makes _maybe_ a 1-2% difference overall.

> Say that you can attain fairly good speeds in transfer (any
> recommendations on good network cards?  haven't really seen - other than
> built on - cards for PCI-E?)

RAID-10 would be most ideal for write performance overall.  If you're
reading far more than writing, then RAID-5 if you don't like the
inefficiency of RAID-10.  If you're just writing from 1-2 systems,
RAID-3 would be most ideal.

Areca has its ARC-12xx series for PCIe x8.  Cost is $400+.

If you have PCI64/PCI-X, the NetCell SR5000 series is high performance
fixed 5-disc configuration RAID-3 (what they call "RAID-XL").  Cost is a
more affordable $200+.

Can't recommend 3Ware except for the 7000/8000/9500S series PCI64/PCI-X,
and you only want to use RAID-10 for those.  I'm still waiting on 3Ware
to produce a stable, newer 9000 series with RAID-5 performance -- the
9500S is basically a 7000/8000 from a RAID-10 standpoint.

> - What protocal would you use? SMB/NFS/SSHFS/??

NFS!  8KiB UDP blocks go 1:1 into 9000 byte Jumbo frames.  You can also
rebuild the kernel with 32KiB blocks for even better performance, but
_always_ use 9000 byte Jumbo frames for it.

> - Remember that is video work, so need as much as possible!

Again, RAID-10 or RAID-5.


-- 
Bryan J. Smith        Professional, technical annoyance
mailto:b.j.smith at ieee.org  http://thebs413.blogspot.com
-------------------------------------------------------
Illegal Immigration = "Representation Without Taxation"