OT: Advice on SATA sought

OT: Advice on SATA sought

[Rudy L. Zijlstra]

Greetings,


I am considering buying some 250G SATA drives (3 in a RAID5 config) for 
multimedia backend storage.
disks will likely be WD SATA WD2500JD unless somebody points out good 
reasons not to. Can get those for about 200 Euro excluding VAT each.
This is going to be used to store interactively accessed MPEG2 video 
files. They will be stored from at least 2 (on short notice 3) sources, 
and simultaously read from 2 or 3 locations. In other words: storage 
backend for a MythTV setup with 2 or 3 backends, and multiple frontends 
using a combination of PVR-250 and PVR-350s. 350 for frontend connected 
to a TV, several frontends using X for output.

The controller i am considering is the Promise SATA TX4.
kernel: 2.6.4 or later from kernel.org on a recent slackware-current 
distro.

Any experience, either with this controller, with SATA, with other 
controllers, please share so I can make a better decision. I've 
currently no real experience with SATA.

Filesystem choice has been made: Reiserfs3. This is going to be a 
production machine, I will not yet test Reiserfs4 on that. Too risky 
considering "comments" i would get on failure...

Regards,

Rudy

Re: OT: Advice on SATA sought

[Hans Reiser]

Rudy L. Zijlstra wrote:

> Greetings,
>
>
> I am considering buying some 250G SATA drives (3 in a RAID5 config) 
> for multimedia backend storage.
> disks will likely be WD SATA WD2500JD unless somebody points out good 
> reasons not to. Can get those for about 200 Euro excluding VAT each.
> This is going to be used to store interactively accessed MPEG2 video 
> files. They will be stored from at least 2 (on short notice 3) 
> sources, and simultaously read from 2 or 3 locations. In other words: 
> storage backend for a MythTV setup with 2 or 3 backends, and multiple 
> frontends using a combination of PVR-250 and PVR-350s. 350 for 
> frontend connected to a TV, several frontends using X for output.
>
> The controller i am considering is the Promise SATA TX4.
> kernel: 2.6.4 or later from kernel.org on a recent slackware-current 
> distro.
>
> Any experience, either with this controller, with SATA, with other 
> controllers, please share so I can make a better decision. I've 
> currently no real experience with SATA.
>
> Filesystem choice has been made: Reiserfs3. This is going to be a 
> production machine, I will not yet test Reiserfs4 on that. Too risky 
> considering "comments" i would get on failure...
>
> Regards,
>
> Rudy
>
>
>
xfs might be better for this than v3, to be honest.  delayed allocation 
matters for this workload.

-- 
Hans

Re: OT: Advice on SATA sought

[Matt Stegman]

Hello,

I've got four WD2000JD drives on a Promise SATA TX4, and they work great.  I
haven't seriously tested the hot swap, although removing and replacing an
unmounted, unused drive seems to work just fine.  But I haven't even tried
swapping in a different sized drive than what I remove.  Now, I also have an
onboard VIA SATA controller on the MSI motherboard... the install kernel
hard locked when probing the controller while a disk was attached.  So I'm
not using that one at all.

SUSE Linux 9 is installed, using SUSE's 2.4.21 kernel, so I don't know if
the 2.6 kernel from kernel.org will support it the same.

FYI - the max streaming bandwidth I get from the software RAID5 array is
~90MB/s reading (single disk read maxes at ~50MB/s).  I can't remember the
write bandwidth, and I appear to have deleted or lost my statistics file.  I
wonder if I'm not hitting the practical limit of a 32-bit/33MHz PCI bus.  So
if you need greater bandwidth, you may want to look into 64-bit PCI.  Maybe
a hardware RAID controller, too - I understand that usually performs better
than the software RAID.

--
Matt Stegman

Re: OT: Advice on SATA sought

[Boyd Waters]

I have had GREAT success with SATA on linux 2.6.0 using the 
sata_promise driver. I have two removable drive trays in a mini-tower, 
and I keep a number of Seagate 160GB drives in rotation. Hot-swap seems 
to WORK - that is, the driver does not lock up - I gracefully unmount 
the filesystem, pop the drive out of the tray, load the new drive, and 
mount the new filesystem. I am not using RAID... at the moment I'm 
using Reiser 3.6 on these but will test Reiser4 Real Soon.

I purchased mine from http://www.newegg.com

22-148-018    HD 160GB|SEAGAT ST3160023AS SATA     $134.00
17-121-114    MOBILERACK SATA KF-72 BEIGE RTL       $12.99
16-102-014    CONTROLLER|PROMISE Sata150 TX2+       $41.00

I would recommend getting the Promise TX4 rather than the TX2+ -- the 
TX2+ has only two SATA ports, two IDE. I intended to get the TX4, which 
has four SATA ports only. You can't daisy-chain SATA like you can with 
(some) SCSI or FireWire, so the TX2+ will support only two drives, not 
really enough for RAID.

  ~ boyd