October 21, 201015 yr Hi folks, I've recently discovered unRAID and i'm in the process of building a server. Thanks to all the helpful information found on these forums and the wiki, I have all of my parts ordered but have been looking for some information on how to expand the number of drives im using, in the future. For motherboard i chose the ASUS M4A785-M. It has 6 onboard SATA ports. I know that i can go with the Supermicro AOC-SASLP-MV8 which will give me 8 additional drives. However, i'm also looking for another sata controller in case i want to add even more capacity down the road. I would install the supermicro in the x16 slot, which leaves a single PCI-E x1 port. Just curious if any of you have any recommendations on a 4 port PCI-E x1 sata controller card ? The only one i can find is the Syba SY-PEX40008 but i've seen some mention of people have issues with this board (ie. unraid doesn't detect drives, boot problems, etc). Any others that are a good choice ? If not, i may have to go with a PCI controller rather than PCI-E, but i'd really like to avoid that if possible. Thanx for the help. -DaViS
October 21, 201015 yr Don't run 4 drives on a PCIe x1 slot, it is too many. You will see lower speeds because of it. Instead, I highly recommend this card: SIL3132 - 2 drives on a PCIe x1 slot It is cheap and reliable, and you won't have any bottlenecks. Your mobo plus the SuperMicro card plus this card will bring you up to 16 drive support. To go past that without bottlenecks you will have to replace the motherboard. Well, I suppose you could add one final drive on a PCI card (but not more than one), if you are desperate. In reality, though, if you don't mind some speed bottlenecks you can cram as many drives as you like onto whatever ports you like.
October 21, 201015 yr Author Actually, that makes a lot of sense Rajahal. I didn't realize that an x1 slot isn't really sufficient for 4 drives. 16 drives is more than enuf for my needs anyway. It will be a while before i even get to that point, if at all. Thanx for the fast reply. -DaViS
October 21, 201015 yr What about using the IDE port? I've seen SATA to IDE adapters that you could install onto a SATA drive so you could connect it to your IDE port. Couldn't you add 2 more drives that way?
October 21, 201015 yr Author I'm assuming using an IDE port could potentially become a bottleneck. Don't really want to get into using adapters. Enabling the addition of 2 more drives with a cheapo PCI-E x1 card is well worth it imho.
October 21, 201015 yr What about using the IDE port? I've seen SATA to IDE adapters that you could install onto a SATA drive so you could connect it to your IDE port. Couldn't you add 2 more drives that way? I'm not 100% sure, but I expect the IDE port wouldn't be good for more than 1 drive anyway. Seems like a last resort type of option to me.
October 21, 201015 yr Seems like a last resort type of option to me. That's how I viewed it as well. I was thinking that the OP wanted more than 16 drives and that's why he was asking about a 4-port PCIe x1 card. I overlooked the post where he said that 16 drives would be more than enough for him. Sorry about that.
October 21, 201015 yr By the time you are running 16 drives on a motherboard you arent going to be able to sustain more that 50MB/s parity reads across the entire array anyway so it won't make any difference. To say it'll cause a bottleneck is either disengenuous or miss informed to keep repeating it is frankly annoying. My system managed to parity check around 80MB/s with 4 drives, 65MB/s with 7 drives, 50MB/s with 12 drives. All of these are fast ports and fast disks, sitting on fast buses. Simple math says more drives = slower parity checks as each drive still has to be read, incurring seek times. By the time you get 16 disks on the system 60MB/s for a pair of disk on a PCI bus or four disks on a PCI-e X1 interface is not going to be a bottleneck. By the time you factor in some 5400rpm green drives, it'll make zip difference on a 16 drive system. A much more real problem with PCI-e x1 4 port cards is they are expensive (for what they are) and few and far between. If you can get hold of one though, it'll serve you well. The Syba SY-PEX40008 won't work, at least it didnt up until 4.6.3, it is a SIL 3124 PCI-X chipset and a PCI-x to PCI-e bridge rather than a native PCI-e card. Cards that I know work are Highpoint PCI-e x1 cards like the RR2300.
October 21, 201015 yr By the time you are running 16 drives on a motherboard you arent going to be able to sustain more that 50MB/s parity reads across the entire array anyway so it won't make any difference. To say it'll cause a bottleneck is either disengenuous or miss informed to keep repeating it is frankly annoying. Huh? If I'm wrong, please educate me.
October 21, 201015 yr As Kaygee says, by the time you have lots of drives, your parity speed is going to diminish anyway. As for 4 SATA devices on a PCIe x1 card, your performance will not suffer all that much. PCIe x1 is capable of 250MB/s in each direction. Unless there are 4 drives capable of doing 120MB/s sustained all the time then the slot will support the 4 drives. It's controller and unRAID compatibility that's the concern. Also note, If PCI @ 33MHZ can do 133MB/s and provide somewhat adequate service, then 4 drives on PCIe will be fine. For the record I tested a Promise TX4 on a PCI @ 66MHZ and the performance was the same as the motherboard ports and an AOC-SATA2-MV8 in a PCI-X slot for 4 drives.
October 21, 201015 yr Huh? If I'm wrong, please educate me. By the numbers, you are not wrong, but in practical use, the warning is not something to be that concerned about.
October 21, 201015 yr Ah, I see. Thanks for the clarification Weebo. Well, davis999, I can still recommend the SIL3132 as being fully compatible with unRAID, plug and play even. If you are satisfied with 16 drives, then I don't think you'll need anything more than that (and the price can't be beat).
October 21, 201015 yr Ah, I see. Thanks for the clarification Weebo. Well, davis999, I can still recommend the SIL3132 as being fully compatible with unRAID, plug and play even. If you are satisfied with 16 drives, then I don't think you'll need anything more than that (and the price can't be beat). Let me add for further consideration. A SIL3132 can support up to 2 Port Multipliers of 5 drives each. So that's almost 10 drives on a PCIe X1. I believe the drives are limited to around 60MB/s when using a port multiplier.
October 21, 201015 yr Author Okay, well thanx for all the input everyone! I didn't even realize that using a port multiplier was an option but good to know. For now, i'm just going to get the SuperMicro 8 port card. If/when i need more, ill prob just go with the 2 port sata. If i decide i need even more than that, well that would require additional hardware upgrades (ie. power supply etc) so that is a not gonna happen any time soon.
October 21, 201015 yr By the time you are running 16 drives on a motherboard you arent going to be able to sustain more that 50MB/s parity reads across the entire array anyway so it won't make any difference. To say it'll cause a bottleneck is either disengenuous or miss informed to keep repeating it is frankly annoying. My system managed to parity check around 80MB/s with 4 drives, 65MB/s with 7 drives, 50MB/s with 12 drives. All of these are fast ports and fast disks, sitting on fast buses. Can you share info regarding the size and the speed of the 12 drives used. I cannot prove it but I believe this to be true for a system with really mixed drive sizes - for example a system with 200, 250, 320, 400, 500, 640, 750, 800GB, 1TB, 1.5TB and 2TB with 2TB parity - this is the worst case example that i can think of. However if someone starts today there is really no point of buying anything less than 2TB and a system with 12 x 2TB drives will have significantly higher parity checks than the one above even if all the HDD are "green"
October 21, 201015 yr I'm not the best candidate because my system is souped up. With 15 drives and a high speed parity drive I get around 110,000K/s to 80,000K with slowest drives as an WD EACS 1TB (10 Drives). It slows down to around 60's near the inner tracks. In comparison when I had 8 drives on another machine. 6 were the WD EACS and I had 1 seagate 1.5TB as parity, I would get around 56,000KB/s So I would think that when you start having large amounts of drives it still weighs on the parity speeds.
October 22, 201015 yr I don't very often pay attention to speeds until the parity sync/generation is done with. My last parity check was done on the 17th of October and it completed with a speed of: 62971K/sec All my drives are 7200RPM with 2 x 2TB Hitachi's in the mix. I am running with 6 drives on motherboard ports and 2 x PCI-e x1 cards with 2 drives each on them.
October 22, 201015 yr My last parity check was done on the 17th of October and it completed with a speed of: 62971K/sec I'm about there too. root@atlas /boot/logs #grep 'sync done' /boot/logs/syslog* /var/log/syslog /boot/logs/syslog-20100906-191909.txt:Aug 2 09:32:55 Atlas kernel: md: sync done. time=33816sec rate=63504K/sec /boot/logs/syslog-20100906-191909.txt:Sep 2 09:33:04 Atlas kernel: md: sync done. time=33837sec rate=63464K/sec /boot/logs/syslog-20100906-191942.txt:Aug 2 09:32:55 Atlas kernel: md: sync done. time=33816sec rate=63504K/sec /boot/logs/syslog-20100906-191942.txt:Sep 2 09:33:04 Atlas kernel: md: sync done. time=33837sec rate=63464K/sec /var/log/syslog:Oct 2 10:06:56 atlas kernel: md: sync done. time=35851sec rate=59899K/sec root@atlas /boot/logs #strings /proc/mdcmd | grep rdevModel rdevModel.0=<no model> rdevModel.1=ST31000340AS rdevModel.2=ST31500341AS rdevModel.3=ST31500541AS rdevModel.4=ST31500341AS rdevModel.5=WDC WD20EADS-00S rdevModel.6= rdevModel.7=WDC WD10EACS-00Z rdevModel.8=WDC WD10EACS-00Z rdevModel.9=WDC WD10EACS-00Z rdevModel.10=WDC WD10EACS-00Z rdevModel.11=ST31500541AS rdevModel.12=WDC WD10EACS-32Z rdevModel.13=WDC WD10EACS-00D rdevModel.14=WDC WD10EADS-00L rdevModel.15=WDC WD10EACS-00Z
October 22, 201015 yr To get back on the original question. Here are 2 cheap 4 port PCIe x1 cards. http://www.span.com/product_info.php?cPath=24_714_2502&products_id=16957 PCI-Express-x1 Card; Int:3x SATA, 1xPATA, 1x eSATA (Marvell 6145) €17.83 +VAT Manufacturer: http://www.ioi.com.tw/products/proddetail.aspx?ProdID=1060085 http://www.span.com/product_info.php?cPath=24_714_2502&products_id=17142 PCI-Express-x1 Card; Int:4x SATA, 1xPATA, €24.60 +VAT Manufacturer: http://www.ioi.com.tw/products/proddetail.aspx?ProdID=1060084 Sadly, as far as I know, the Marvell 88SE6145 chip is not supported in UNRAID. I hope someone can prove I am wrong!! Would be a perfect low-cost solution for PCIe x1 slots!
October 22, 201015 yr http://www.span.com/product_info.php?cPath=24_714_2502&products_id=17142 PCI-Express-x1 Card; Int:4x SATA, 1xPATA, €24.60 +VAT Manufacturer: http://www.ioi.com.tw/products/proddetail.aspx?ProdID=1060084 I've been waiting for one of these to come into stock for over 12 months... I agree this should work but Marvell 88SE614x driver is "picky" to say the least and at that price not the end of the world if it doesnt. Can you share info regarding the size and the speed of the 12 drives used. No problem, 7200 RPM 500GB 630AS Seagates x4, Samsung 1TB HD103UJ 7200RPM x 4, Seagate 542as 5900RPM 2TB x 2, WD WD20EADS 2TB 5400RPM x1, Samsung SAMSUNG HD203WI 5400RPM 2TB x1. Parity is currently another Samsung SAMSUNG HD203WI 5400RPM 2TB x1. Parity is currently hooked to the m/b, with only the cache drive for company. Last parity check was run with 4 x 500GB seagates on the M/B ports with parity and cache drives for company. Other six running on PCI-X Highpoint RR1820a. Next parity check will be run with cache and parity on the motherboard and all other drives on a pair of RR1820a PCI-X cards. Running on different buses but at 100MHZ not the 133MHZ of a single card. I'll report back what it does in this config. Sucks!!! Oct 23 13:07:30 Tower kernel: md: sync done. time=55063sec rate=35477K/sec Oct 23 13:07:30 Tower kernel: md: recovery thread sync completion status: 0 If it didnt take so long to run I'd slap in the RR2300 and put four drives on that just for kicks...
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