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PCI Express SATA Controller NO RAID
- Thread starter trmentry
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ring.of.steel
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you could get a cheap silicon image 4 port controller for like $15
get 2 even
get 2 even
unhappy_mage
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The Highpoint 2320 doesn't have real RAID on it - it's just a software raid controller with driver-based RAID - but it's still $250. For that price you might as well buy an LSI SAS controller. I don't know of anything else that's cheaper.
Trepidati0n
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Have you considered a port multiplier?
unhappy_mage
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Found one - $70 for four ports plus two internal. It's only got one lane host interface, which is either convenient or limiting, depending on your situation.
Ok... is it possible to use that card as just a controller... disable all the raid functions?
Nope. I wish Supermicro would come out with their new PCI-E revisions... that would be awesome.
Trepidati0n
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Maybe a year or 6 months ago, however the winds have shifted (Suse 10.3). May wish to ask mikesm a few questions or to post in here.
The new libata support in newer kernels handles these controllers quite well. I have had luck with both the syba (el cheapo <$20) and SIIG (cheapo) 3132 based pci-e controllers. They work out of the box with suse 10.3. And they support port multipliers too. I have become a big fan of PMP's, and if you have just one PMP, you can hook 5 drives to 1 3132 sata port.
If you aren't running suse 103. or another distro that has the patches already installed, you can find patches for the generic kernel at http://home-tj.org/wiki/index.php/Libata-tj-stable. Tejun is owed a debt of gratitude by all linux NAS builders for making port multiplier and hotswap support work in linux.
There are some other jmicron based pci-e controllers that should work too, but the code is more mature for the 3132, and the price difference is minimal, so why bother...
I have 2 5in3 hot swap cages filled with drives all being driven by a single 3132 based pci-e controller with 2 internal sata ports. This is definitely the way to go instead of 8 port highend cards. Motherboards with AHCI ports also work fine for this.
PS You really want to avoid plain old PCI based controllers, as the PCI bus becomes a bottleneck when you hook more than 2-3 drives to a PCI based controller. PCI-E is the way to go for performance, and again, there is maybe a $5 difference in price, so no reason to use PCI now at all, unless you are running an ancient motherboard, in which case you likely will have other problems.
One more thing, don't worry about performance issues with port multipliers. The SATA 2 spec can handle 5 drives with absolutely no problem in terms of bandwidth.
Real world filesystem performance under XFS is excellent. Before I added some new drives, I benchmarked filesystem performance north of 200 MB/s reads and something like 180 MB/s writes to a 5 disk SATA raid array through a port multiplier. Needless to say, I was pretty happy with the performance for such a cheap config. This included lvm2 overhead no less. And I made sure the files that were being used to test the filesystem speed were so large that it's not just RAM buffering. For smaller files that stay in memory, the number was much higher.
Real world filesystem performance under XFS is excellent. Before I added some new drives, I benchmarked filesystem performance north of 200 MB/s reads and something like 180 MB/s writes to a 5 disk SATA raid array through a port multiplier. Needless to say, I was pretty happy with the performance for such a cheap config. This included lvm2 overhead no less. And I made sure the files that were being used to test the filesystem speed were so large that it's not just RAM buffering. For smaller files that stay in memory, the number was much higher.
Not off hand. I think Ubuntu had it in the previous release, so I doubt it wouldn't be in the latest. The only question is if the distro had AHCI support as well or the earlier si3132 only. I would be surprised if it wasn't the latest version. I use suse only so I don't have personal experience with the others.
Making a new kernel isn't that big a deal in my experience. Do you have some esoteric hardware where installing a generic kernel with the libata-tj patches would be a problem?
Making a new kernel isn't that big a deal in my experience. Do you have some esoteric hardware where installing a generic kernel with the libata-tj patches would be a problem?
The distro really doesn't matter. The drivers you are talking about are in the main kernel tree, so anything that uses a recent kernel (>2.6.19 in this case), and that has those drivers enabled, will work. So Gentoo supports it by definition, since you would configure and build your own kernel.
http://www.addonics.com/products/host_controller/ad5sapm.asp
This is one of the few internal cards that I have found. It seems like the majority of the port multipliers are geared towards eSATA enclosures.
This is one of the few internal cards that I have found. It seems like the majority of the port multipliers are geared towards eSATA enclosures.
These are what I use. The 3726 based PMP's work well in my experience.
They appear to be a bit more expensive then the Promise 4-port SATA controller cards I was looking at. I think these will be worth the extra cost since they will work well with the 5-drive SATA back planes, without the bottleneck of the PCI controller cards.
Exactly right. Super cheap 4 port PCI based SATA controllers are out there, but burn slots have and the PCI bus limit. PMP's hooked to PCIE SATA 2 ports are very fast, and very good bang for buck.