2x i-RAM RAID0, The Irony

Copper · Post by **Copper** » Sun Apr 09, 2006 2:11 pm

I finally managed to get a working RAID0 with the i-RAMs. Unfortunately, I had to do it with a Siig 3112r PCI card. I have a slower drive, but 8GB instead of 4.

CPU usage is surpisingly low for a software RAID. Transfer isn't too bad considering it's going over the PCI bus. Latency has become measurable in HD Tach at 0.1ms. Here is a look: RAID bench. Compare that to a single i-RAM running over the ICH5R: Single drive bench.

Intel's ICH5R southbrigde on my Intel 875PBZ board fails to run the i-RAM in RAID. I get a BSOD as soon as WindowsXP's setup attempts to access the drive. I had the same thing happen on Via's 964 southbridge on an Asus P4S800D-X motherboard. Ironically, Gigabyte lists the 964 as compatable for RAID.

It was fun to test, but since I don't necessarily need the drive to be 8GB, I'll go back to running the drives independantly off the ICH5R. At least we know that it can be done.

Butcher · Post by **Butcher** » Sun Apr 09, 2006 2:30 pm

Problem with the i-ram is the bus limitations. I wonder how well a similar device hooked up to u320 would perform.

Copper · Post by **Copper** » Sun Apr 09, 2006 2:43 pm

Butcher wrote:Problem with the i-ram is the bus limitations. I wonder how well a similar device hooked up to u320 would perform.

Even SATAII would be a nice jump.

Butcher · Post by **Butcher** » Sun Apr 09, 2006 2:52 pm

Interesting to see that even with a nominal 1.5 Gbps bus the i-ram tops out just over 130 MB/s. I wonder if that SATA limits or the southbridge bus?

Copper · Post by **Copper** » Sun Apr 09, 2006 3:48 pm

Butcher wrote:Interesting to see that even with a nominal 1.5 Gbps bus the i-ram tops out just over 130 MB/s. I wonder if that SATA limits or the southbridge bus?

I think the southbridge bus is 2GBytes/s compared to SATA's 1.5Gbits/s -- less than 1/10th of the southbridge. I think it's just a matter of there always being overhead and latency, whether it's SCSI, LAN, PCI, ATA, or SATA. Data throughput is always below total bus bandwidth.

Copper · Post by **Copper** » Sun Apr 09, 2006 5:24 pm

I'm giving an Asus P4P800-E Deluxe a try. It has an Intel 865PE chipset and ICH5R southbridge, with an additional Promise PDC20378 PATA/SATA RAID controller. My luck, the Promise controller will work, but is piped through the PCI bus.

Worst case, the board will give me some over/underclocking and volting options that are severly lacking in my Intel board. Not to mention I keep getting coil noises off this Intel board.

Sure would be sweet to get these i-RAMs RAIDed through independant SATA channels. Should get about 260MB/s with very little latency.

Eunos · Post by **Eunos** » Mon Apr 10, 2006 1:27 am

Nice work Copper - it's funny you mention this, because I was just reading my i-RAM owners manual and it mentioned that they can be run in RAID, but reduces HD size by 500-1000 mbs.

So your getting slower speeds through the PCI card? I still have been meaning to test mine, but am still celebrating that your suggestion got rid of that godawful 1.5 gb tmp file.

Copper · Post by **Copper** » Mon Apr 10, 2006 4:03 am

I read the very same thing about loosing drive space, but I'm getting all 8GB.

Eunos · Post by **Eunos** » Mon Apr 10, 2006 6:16 pm

Speaking of losing space, the manual also said that the formatted drive loses some space. I see pretty much the full 8 gig there, which confirms my 512 isn't working. I have bought a new 1 gb stick so I'll have the full 4 gig total and can call it a day!

PizPump · Post by **PizPump** » Wed Apr 12, 2006 9:26 am

My raptor (non-optimized) bench for comparison's sake.

Uwackme · Post by **Uwackme** » Sun Apr 16, 2006 9:44 am

Absolutely NO DATA goes over the PCI bus with an iRAM.

It is a stand alone SATA-I device, it plugs into the PCI slot for a cheap mounting method AND to tie into the 5Volt Standby power source, that keeps the ram happy while you are shutdown.

The PCI bus bandwidth has NOTHING what so ever to do with iRAM.

The SATA-I bus has everything to do with it. iRAM, esp two of them in raid0 should be able to achive the 150MB/s maximum.

If you are stuck using a PCI based sata controller, then you can hit the 133MB/s max of the PCI bus, and this is the case on any Sil3112/3114 based controller, since even the ones on the motherboard are STILL PCI cards, just not plugged into connectors, it's all in etch on the motherboard.

You need a NF4 sataII controller, or a highend Intel motherboard with native sata to remove the speed limits of PCI bus based controllers.

NF4 with that setup should be able to hit BEYOND 150MB/s transfer rate with a pair of iRAMs in raid0.

Copper · Post by **Copper** » Sun Apr 16, 2006 1:24 pm

Uwackme wrote:You need a NF4 sataII controller, or a highend Intel motherboard with native sata to remove the speed limits of PCI bus based controllers.

There-in lies the irony. My $200 Intel board w/ICH5R southbridge wont run the i-RAMs in RAID but my $12 3112r PCI card will. I can get RAID, but only if I take a performance hit.

I wish I had an ICH6R or 7R board to try it on. Unfortunaetly I'd have to update a lot of other hardware to do it. We'll see how the new Asus board does.

Copper · Post by **Copper** » Tue Apr 18, 2006 5:28 pm

Someone please tell me what I'm doing wrong.

I have the Asus P4P800-E Deluxe. I created a RAID driver floppy. I enable the ICH5R RAID in the BIOS. I reboot and configure the RAID. It shows the two i-RAMs in RAID0. I go back into the BIOS and set the new RAID set as the first hard disk.. From here both the RAID controller and the BIOS recognize the RAID set. But...

I throw in the XP cd, hit F6, specify the RAID driver, XP copies the files, and when it gets to the screen where you can select which drive to install on it shows my PATA drive and the individual i-RAMs - no RAID set. After a second try, and getting the same results I went ahead and selected one of the i-RAMs. Windows formated the single i-RAM and copied all the files onto it. Shut down, restart, no boot disk. It's a RAID set again.

Copper · Post by **Copper** » Wed Apr 19, 2006 2:27 pm

Well, the onboard Promise controller works in RAID, but, of course, it's piped through the PCI bus and gets the same ~112MB/s as the SiiG PCI card.

2x i-RAM RAID0, The Irony

2x i-RAM RAID0, The Irony

huh?

Re: huh?