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Linux HW and SW RAID Benchmarked
An anonymous reader writes "A Norwegian site has written up an article with various RAID solutions benchmarked using both bonnie++ and dbench. The result shows a lot of surprises, especially when comparing low end sw RAID with high end hw RAID. The text is in Norwegian but the numerous graphs are self explanatory. It does look like a few kernel drivers need a little tweaking."
Anyone know an internet translator that supports Norwegian? Or even a Norwegian? It would be nice to have a translation so we don't have to sit around making uninformed comments about what we can't understand...
Oh, wait...
# cat
Damn, my RAM is full of llamas.
My bonnie++ was used by Norwegians, To see how fast my RAID could be, My bonnie++ was used by Norwegians, ...but was bonnie++ written in C?
Paleotechnologist and connoisseur of pretty shiny things.
here
Damn. I've been a geek too long. After all these years I know understand how my pointy haired boss feel when attempting to read a technical article.
~~ What's stopping you?
Ok, who the fuck allowed this submission to go through? A whole 2% of Slashdot readership will probably be able to read this, the rest of us are left in the dark. Are longer bars better, or worse? WTFOMGBBQ?!
Jeg skal ikke gå så langt som å si at man burde satse på verken SATA, billige kontrollere eller software-RAID.
In english; I will not go as far as to recommend SATA, cheap controllers or software-RAID.
Seriously, is this frontpage news on Slashdot? I'm a native speaker, and the article did not impres s me much. In fact, there is nothing newsworthy about the article, and the author admits it in the conclusion. Not very insightful, the article is crearly written by an amateur. In fact, in my opinion, the only reason this was submitted to Slashdot, is because hwb.no is a new site, which is trying desperately to get visitors.
A møøse once bit my sister...
It would be nice to have a translation so we don't have to sit around making uninformed comments about what we can't understand...
Somehow, I don't think a translation would keep them away.
-"One machine can do the work of fifty ordinary men. No machine can do the work of one extraordinary man." -EH
From TFA: To innebygde gigabit-nettverkskort
That is just the coolest; I am hereby recommending everyone refer to networking as 'nettverkskort'. It might be cold in Norway, but they have some awesome sounding linguistic constructions!
PS - What the heck is nettverkskort, exactly? 'Networking'? 'Network Adapter'? Heck, I don't know what it is; I just know I like it.
This is not a very good review, they have used kernel 2.6.8, 2.6.11 has many fixes upon previous releases in regards to RAID and md (software raid) drivers.
Lets get a review that uses 2.6.11, then lets see where we are.
Hey, this is my sig, if you don't like it, STOP READING MY POSTS!
Now, give it to a non-Norwegian speaking geek, and a non-Geek Norwegian speaker.
Who do you think will have more luck making heads or tails of it?
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
Drilling through the article with my utterly minimal norwegian (Prarie Home Companion + German + exposure to Danish coworkers), I think I've distilled the following:
Cache on the LSI RAID controller is 1/2 the adaptec. Performance is comparable, though not equivalent.
All of the controllers are 64-bit.
Adaptec SCSI is good for both hardware RAID and software RAID.
LSI has good hardware SCSI RAID only.
Don't use current SATA controllers (RAID or Otherwise) for best performance.
Does anybody with access to a good collection of modern hardware care to re-run this test in a language that Babelfish understands?
the more accurate the calculations became, the more the concepts tended to vanish into thin air. R. S. Mulliken
Ok, here is a rough translation:
I have wanted to test some real SATA controllers against SCSI controllers for some time now, to see how good SATA has become. I once thought that cheap controllers like Sil 3114 is cheap crap that manufacturers put on their boards simply to provide SATA-support, and that software RAID was a cheap, but insufficient solution, since I have followed the principle that hardware does the job best. "A more expensive controller, means more hardware", was my initial guess, but it seems that even the cheap controllers are worthy. Software RAID also performs very well. SATA is no longer some gag for disk systems that are supposed to perform well, and many myths have been dispelled by my test.
I will not go as far as to say that you shall place your bet on cheap controllers or software RAID. The reason is simple, in a expensive controller, there is much more functionality, that a cheap controller can just dream about. Functionality like hot-spare drives and hot-swap, just to mention some. I do not want to recommend SATA over SCSI in a while either. The lifespan of a SCSI drive is in most casese many times as long as a vanilla SATA-disk. When you choose a solution, it should last. If you have machines that has a big fat controller, RAID50, then SATA might be something for you. If you have a machine that needs redundancy on the internal drives, but where changing controllers, or even buying them in the first place has been in the way, then software RAID might be the solution for you.
I shall be careful to mock the LSI controller, as I think there might be a problem with the way the test machine talks to it. I think the new Megaraid driver in the kernel might be the problem. Either it needs to mature, or it is simply that it does not like 64-bit Linux. I have not tampered too much with the default settings, but it runs superparanoid verification algorithms when it sends and recieves data. I have not fleshed the BIOS on any of the controllers.
Adaptecs controllers do very well. Everything was not perfect with them, and the aacraid driver in the kernel was too old for both of the controllers. From their website, I found something that looked like source code (Adaptec seems to rely on 100% RPM based distros), and I could bouild my own module. After that, no problem. A little minus is that the aacraid does not report how long the controller has gotten in building the array after you have set up a RAID. By looking at the SCSI-BIOS after some hours, I got to verify that the array was built.
I want to warn everyone that is going to buy a controller. Carefully check that the controller is supported in the kernel! I use Google to check for references to the card on mailing lists, but that does not help much when you have Debian, and all that exist is binary RedHat drivers.
Now, run to your console and test your disk system. This test does only give you indications on what to choose. I allow myself to give you one final advice: Run tests for yourself.
Dvorak on Doomtech
A 3ware 12 port SATA card and a three port U320 SCSI card with four drives on each port both support the same number of drives. Except the SATA card will probably be 1/3 the price, the SATA drives will be 1/10 the cost per GB, and have higher transfer rates.
SATA does have real command queuing. There are real hotswap SATA drive bays. It's true the cables can't be as long, but since you only need to connect once device per cable instead of 4 or more, it's usually easier to connect. And believe me, I know my way around a SCSI cable.