How I built a 2.8TB RAID storage array
My 2.8TB RAID 5 array is finally up and running. Here I'll discuss my
initial intended specifications, what I actually ended up with, and associated commentary. Please see URL:http://groups.google.ca/groups?selm=slrnch28at.j0n.ylee%40pobox.com and URL:http://groups.google.ca/groups?selm=slrncu34ip.55k.ylee%40pobox.com for background material. STORAGE MEDIUM Initial: Eight 250GB SATA drives. Actual: Nine 400GB PATA drives; eight for use, one as a cold spare. Why: Found a stupendous sale at CompUSA Christmas week; just-released-in-November Seagate Barracuda 7200.8 400GB PATA drives at $230 each, with no quantity limitation . I'd have loved to have gone with the SATA model, but given that Froogle lists the lowest price for one at $350 (the PATA model retails at $250-350), it was an easy choice. CASE Initial: Antec tower case. Actual: Antec 4U rackmount case. Why: I'd always thought of rackmounts as unsuitable for anyone with an actual rack sitting in their data center, but after realizing that a rackmount case is simply a tower case sitting on its size, it was an easy decision given the space advantages. The Antec case here comes with Antec's True Power 550W EPS12V power supply, and both have great reputations. In practice, I found that the Antec case was remarkably easy to open up (one thumbscrew), work with (all drive cages are removable), and roomy. MOTHERBOARD Initial: Unspecified, but probably something Athlon-based and cheap. Actual: Gigabyte X5DAL-G Intel server motherboard Why: I became convinced that the sheer volume of the PCI traffic generated by my proposed array under software RAID would overwhelm any non-server motherboard, resulting in errors. In addition, I wanted PCI-X slots for optimal performance. Even though I think AMD in general offers much better bang for the buck, since I didn't want to spend the $$$ for Opteron, a Xeon motherboard with an Intel server chipset was the best comprimise. CONTROLLER CARDS Initial: Two Highpoint RocketRAID 454 cards. Actual: Two 3Ware 7506-4LP cards. Why: I needed PATA cards to go with my PATA drives, and also wanted to put the two PCI-X slots on my motherboard to use. I found exactly two PATA PCI-X controller cards: The 3Ware, and the Acard AEC-6897. Given that the Acard's Linux driver compatibility looked really, really iffy, I went with the 3Ware. I briefly considered the 7506-8 model, which would've saved me about $120, but figured I'd be better off distributing the bandwidth over two PCI-X slots rather than one. SOFTWARE Initial: Linux software RAID 5 and XFS or JFS. Actual: Linux software RAID 5 and JFS. Why: Initially I planned on software RAID knowing that the Highpoint (and the equivalent Promise and Adaptec cards) didn't do true hardware RAID. Even after switching over to 3Ware (which *does* do true hardware RAID), everything I saw and read convinced me that software RAID was still the way to go for performance, long-term compatibility, and even 400GB extra space (given I'd be building one large RAID 5 array instead of two smaller ones). I saw *lots* of conflicting benchmarks on whether XFS or JFS was the way to go. Ultimately URL:http://pcbunn.cacr.caltech.edu/gae/3ware_raid_tests.htm pushed me toward JFS, but I suspect I could have gone XFS with no difficulty whatsoever. COST As implied above, I paid $2070 plus sales tax for the drives. I lucked out and found a terrific eBay deal for a prebuilt system containing the above-mentioned case and motherboard, two Xeon 2.8GHz CPUs, a DVD drive, and 2GB memory for $1260 including shipping labor aside, I'd have paid *much* more to build an equivalent system myself. The 3Ware cards were $240 each, no shipping or tax, from Monarch Computer. With miscellaneous costs (such as a Cooler Master 4-in-3 drive cage and an 80GB boot drive from Best Buy for $40 after rebates), I paid under $4100, tax and shipping included, for everything. At $1.46/GB *plus* a powerful dual-CPU system, boatloads of memory, and a spare drive, I am quite satisfied with the overall bang for the buck. ASSEMBLY: HARDWARE I spent most of the assembly time on the physical assembly part; it's astonishing just how long the simple tasks of opening up each retail-boxed drive, screwing the drive into the drive cage, putting the cage into the case, removing the cage and the drive when you realize you've put the drive in with the wrong mounting holes, reinstalling the drive and cage, etc., etc. take! My studio apartment still looks like a computer store exploded inside it. 3Ware wisely provides PATA master-only cables with its cards, which saved some room, but my formerly-roomy case nonetheless looks like the rat's nest to end all rat's nests inside. ASSEMBLY: SOFTWARE I'd gone ahead and installed Fedora Core 3 with the boot drive only before the controller cards arrived. The 3Ware cards present each PATA drive as a SCSI device (/dev/sd[a-h]). Once booted, I used mdadm to create the RAID array (no partitions; just whole drives). While the array chugged along to create the parity information (about four hours), I then created one large LVM2 volume group and logical volume on top of the array, then created one large JFS file system. By the way, I found a RAID-related bug with Fedora Core's bootscripts; see URL:https://bugzilla.redhat.com/beta/show_bug.cgi?id=129633). RESULTS 'df -h': /dev/mapper/VolGroup01-LogVol00 2.6T 221G 2.4T 9% /mnt/newspace 'mdadm --detail /dev/md0': Version : 00.90.01 Creation Time : Wed Feb 16 01:53:33 2005 Raid Level : raid5 Array Size : 2734979072 (2608.28 GiB 2800.62 GB) Device Size : 390711296 (372.61 GiB 400.09 GB) Raid Devices : 8 Total Devices : 8 Preferred Minor : 0 Persistence : Superblock is persistent Update Time : Sat Feb 19 16:26:34 2005 State : clean Active Devices : 8 Working Devices : 8 Failed Devices : 0 Spare Devices : 0 Layout : left-symmetric Chunk Size : 512K Number Major Minor RaidDevice State 0 8 0 0 active sync /dev/sda 1 8 16 1 active sync /dev/sdb 2 8 32 2 active sync /dev/sdc 3 8 48 3 active sync /dev/sdd 4 8 64 4 active sync /dev/sde 5 8 80 5 active sync /dev/sdf 6 8 96 6 active sync /dev/sdg 7 8 112 7 active sync /dev/sdh Events : 0.319006 'bonnie++ -s 4G -m 3ware-swraid5-type -p 3 ; \ bonnie++ -s 4G -m 3ware-swraid5-type-c1 -y & \ bonnie++ -s 4G -m 3ware-swraid5-type-c2 -y & \ bonnie++ -s 4G -m 3ware-swraid5-type-c3 -y &' (To be honest these results are just a bunch of numbers to me, so any interpretations of them are welcome. I should mention that these were done with three distributed computing [BOINC, mprime, and Folding@Home] projects running in the background. Although 'nice -n 19' each, they surely impacted CPU and perhaps disk performance somewhat.) Version 1.03 ------Sequential Output------ --Sequential Input- --Random- -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks-- Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP 3ware-swraid5-ty 4G 15749 50 15897 8 7791 6 10431 49 20245 11 138.1 2 ------Sequential Create------ --------Random Create-------- -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete-- files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP 16 381 6 +++++ +++ 208 3 165 7 +++++ +++ 192 4 3ware-swraid5-type-c1,4G,15749,50,15897,8,7791,6,10431,49,20245,11,13 8.1,2,16,381,6,+++++,+++,208,3,165,7,+++++,+++,192 ,4 done. Version 1.03 ------Sequential Output------ --Sequential Input- --Random- -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks-- Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP 3ware-swraid5-ty 4G 13739 46 17265 9 7930 6 10569 50 20196 11 146.7 2 ------Sequential Create------ --------Random Create-------- -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete-- files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP 16 383 7 +++++ +++ 207 3 162 7 +++++ +++ 191 4 3ware-swraid5-type-c2,4G,13739,46,17265,9,7930,6,10569,50,20196,11,14 6.7,2,16,383,7,+++++,+++,207,3,162,7,+++++,+++,191 ,4 done. Version 1.03 ------Sequential Output------ --Sequential Input- --Random- -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks-- Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP 3ware-swraid5-ty 4G 13288 43 16143 8 7863 6 10695 50 20231 12 149.6 2 ------Sequential Create------ --------Random Create-------- -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete-- files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP 16 537 9 +++++ +++ 207 3 161 7 +++++ +++ 188 4 3ware-swraid5-type-c3,4G,13288,43,16143,8,7863,6,10695,50,20231,12,14 9.6,2,16,537,9,+++++,+++,207,3,161,7,+++++,+++,188 ,4 FINAL NOTES, THOUGHTS, AND QUESTIONS I've noticed that over sync NFS, initiating a file copy from my older Athlon 1.4GHz system to the RAID array system is *much, much, much* (seconds as opposed to many minutes)slower than if I initiate the copy in the same direction but from the array system. Why is this? I almost went with the SATA (8506) version of the 3Ware cards and a bunch of PATA-SATA adapters in order to maintain compatibility with future drives, likely to be SATA only. However, a colleague pointed out the foolishness of paying $200 extra ($120 for eight adapters plus $80 for the extra cost of the SATA cards) in order to (possibly) futureproof a $480 investment. I was concerned that the drives (and the PATA cables) would cause horrible heat and noise issues. These, surprisingly, didn't occur; according to 'sensors', internal temperatures only rose by a few degrees, and the server is just as (very) noisy now as pre-RAID drives. I think I'l be able to get away with stuffing the array inside my hall closet after all. The server, before I put the cards and RAID drives into the system but with the distributed-computing projects putting the CPU at 100% utilization, took the power output on my Best Fortress 750VA/450W UPS from about 55% to about 76%. With the RAID up and running and again with 100% CPU utilization, output is 87-101% with the median at perhaps 93%. I realize I really ought to invest in another UPS, but with these figures I'm tempted to get by on what I currently have. Yes, I could've saved a considerable amount of money had I gone with, say, a used dual PIII server system with regular PCI slots (and, thus, $80 Highpoint RAID cards, again for the four PATA channels and not for their RAID functionality per se) and 512MB. And I suspect that for a home user like me performance wouldn't have been too much less. But I like to buy and build systems I can use for years and years without having to bother with upgrading, and figure I've made a long-term (at least 4-5 years, which is long term in the computer world) investment that provides me with much more than just storage functionality. And again, $1.46/GB is hard to beat. -- Read my Deep Thoughts @ URL:http://www.ylee.org/blog/ PERTH ---- * Cpu(s): 6.7% us, 3.7% sy, 0.4% ni, 75.4% id, 12.3% wa, 1.4% hi, 0.0% si Mem: 515800k total, 511628k used, 4172k free, 5812k buffers Swap: 2101032k total, 13152k used, 2087880k free, 163928k cache |
What kind of cables did 3ware provide, regular flat ribbon or round cables?
If round cables, can you tell if they are just ribbons rolled up? I had a bunch of questions but I read your post again and pretty much everything was answered. Maybe even the cable question but I didn't see it. While everything is still fresh in your mind, make sure you label the drives so you are absolutely sure which drive is which. When I had a drive failure with my measly 500GB raid 5 array, it was a big concern of mine when I pulled a drive and replaced it. Not knowing EXACTLY what would happen should I pull the wrong drive and replace it. I can only imagine my sweating on which of the 8 drives to replace! Like they say, measure twice, cut once! For me, choosing between 2 hardware arrays or 1 software array would have been a big decision, the decision of all decisions. When did you finally make the decision? Was the machine already assembled before you really knew which way you would go? Isn't current tech/$ great? A guy can do some really, really cool stuff with a reasonable budget. I mean $4100 is a lot of money, but what you have is amazing. Great project by the way. --Dan "Yeechang Lee" wrote in message ... My 2.8TB RAID 5 array is finally up and running. Here I'll discuss my initial intended specifications, what I actually ended up with, and associated commentary. Please see CONTROLLER CARDS Initial: Two Highpoint RocketRAID 454 cards. Actual: Two 3Ware 7506-4LP cards. Why: I needed PATA cards to go with my PATA drives, and also wanted to put the two PCI-X slots on my motherboard to use. I found exactly two PATA PCI-X controller cards: The 3Ware, and the Acard AEC-6897. Given that the Acard's Linux driver compatibility looked really, really iffy, I went with the 3Ware. I briefly considered the 7506-8 model, which would've saved me about $120, but figured I'd be better off distributing the bandwidth over two PCI-X slots rather than one. SOFTWARE Initial: Linux software RAID 5 and XFS or JFS. Actual: Linux software RAID 5 and JFS. Why: Initially I planned on software RAID knowing that the Highpoint (and the equivalent Promise and Adaptec cards) didn't do true hardware RAID. Even after switching over to 3Ware (which *does* do true hardware RAID), everything I saw and read convinced me that software RAID was still the way to go for performance, long-term compatibility, and even 400GB extra space (given I'd be building one large RAID 5 array instead of two smaller ones). I saw *lots* of conflicting benchmarks on whether XFS or JFS was the way to go. Ultimately URL:http://pcbunn.cacr.caltech.edu/gae/3ware_raid_tests.htm pushed me toward JFS, but I suspect I could have gone XFS with no difficulty whatsoever. COST As implied above, I paid $2070 plus sales tax for the drives. I lucked out and found a terrific eBay deal for a prebuilt system containing the above-mentioned case and motherboard, two Xeon 2.8GHz CPUs, a DVD drive, and 2GB memory for $1260 including shipping labor aside, I'd have paid *much* more to build an equivalent system myself. The 3Ware cards were $240 each, no shipping or tax, from Monarch Computer. With miscellaneous costs (such as a Cooler Master 4-in-3 drive cage and an 80GB boot drive from Best Buy for $40 after rebates), I paid under $4100, tax and shipping included, for everything. At $1.46/GB *plus* a powerful dual-CPU system, boatloads of memory, and a spare drive, I am quite satisfied with the overall bang for the buck. ASSEMBLY: HARDWARE I spent most of the assembly time on the physical assembly part; it's astonishing just how long the simple tasks of opening up each retail-boxed drive, screwing the drive into the drive cage, putting the cage into the case, removing the cage and the drive when you realize you've put the drive in with the wrong mounting holes, reinstalling the drive and cage, etc., etc. take! My studio apartment still looks like a computer store exploded inside it. 3Ware wisely provides PATA master-only cables with its cards, which saved some room, but my formerly-roomy case nonetheless looks like the rat's nest to end all rat's nests inside. ASSEMBLY: SOFTWARE I'd gone ahead and installed Fedora Core 3 with the boot drive only before the controller cards arrived. The 3Ware cards present each PATA drive as a SCSI device (/dev/sd[a-h]). Once booted, I used mdadm to create the RAID array (no partitions; just whole drives). While the array chugged along to create the parity information (about four hours), I then created one large LVM2 volume group and logical volume on top of the array, then created one large JFS file system. By the way, I found a RAID-related bug with Fedora Core's bootscripts; see URL:https://bugzilla.redhat.com/beta/show_bug.cgi?id=129633). RESULTS 'df -h': /dev/mapper/VolGroup01-LogVol00 2.6T 221G 2.4T 9% /mnt/newspace 'mdadm --detail /dev/md0': Version : 00.90.01 Creation Time : Wed Feb 16 01:53:33 2005 Raid Level : raid5 Array Size : 2734979072 (2608.28 GiB 2800.62 GB) Device Size : 390711296 (372.61 GiB 400.09 GB) Raid Devices : 8 Total Devices : 8 Preferred Minor : 0 Persistence : Superblock is persistent Update Time : Sat Feb 19 16:26:34 2005 State : clean Active Devices : 8 Working Devices : 8 Failed Devices : 0 Spare Devices : 0 Layout : left-symmetric Chunk Size : 512K Number Major Minor RaidDevice State 0 8 0 0 active sync /dev/sda 1 8 16 1 active sync /dev/sdb 2 8 32 2 active sync /dev/sdc 3 8 48 3 active sync /dev/sdd 4 8 64 4 active sync /dev/sde 5 8 80 5 active sync /dev/sdf 6 8 96 6 active sync /dev/sdg 7 8 112 7 active sync /dev/sdh Events : 0.319006 'bonnie++ -s 4G -m 3ware-swraid5-type -p 3 ; \ bonnie++ -s 4G -m 3ware-swraid5-type-c1 -y & \ bonnie++ -s 4G -m 3ware-swraid5-type-c2 -y & \ bonnie++ -s 4G -m 3ware-swraid5-type-c3 -y &' (To be honest these results are just a bunch of numbers to me, so any interpretations of them are welcome. I should mention that these were done with three distributed computing [BOINC, mprime, and Folding@Home] projects running in the background. Although 'nice -n 19' each, they surely impacted CPU and perhaps disk performance somewhat.) Version 1.03 ------Sequential Output------ --Sequential Input- --Random- -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks-- Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP 3ware-swraid5-ty 4G 15749 50 15897 8 7791 6 10431 49 20245 11 138.1 2 ------Sequential Create------ --------Random Create-------- -Create-- --Read--- -Delete-- -Create-- --Read--- -Del ete-- files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP 16 381 6 +++++ +++ 208 3 165 7 +++++ +++ 192 4 3ware-swraid5-type-c1,4G,15749,50,15897,8,7791,6,10431,49,20245,11,13 8.1,2,1 6,381,6,+++++,+++,208,3,165,7,+++++,+++,192,4 done. Version 1.03 ------Sequential Output------ --Sequential Input- --Random- -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks-- Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP 3ware-swraid5-ty 4G 13739 46 17265 9 7930 6 10569 50 20196 11 146.7 2 ------Sequential Create------ --------Random Create-------- -Create-- --Read--- -Delete-- -Create-- --Read--- -Del ete-- files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP 16 383 7 +++++ +++ 207 3 162 7 +++++ +++ 191 4 3ware-swraid5-type-c2,4G,13739,46,17265,9,7930,6,10569,50,20196,11,14 6.7,2,1 6,383,7,+++++,+++,207,3,162,7,+++++,+++,191,4 done. Version 1.03 ------Sequential Output------ --Sequential Input- --Random- -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks-- Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP 3ware-swraid5-ty 4G 13288 43 16143 8 7863 6 10695 50 20231 12 149.6 2 ------Sequential Create------ --------Random Create-------- -Create-- --Read--- -Delete-- -Create-- --Read--- -Del ete-- files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP 16 537 9 +++++ +++ 207 3 161 7 +++++ +++ 188 4 3ware-swraid5-type-c3,4G,13288,43,16143,8,7863,6,10695,50,20231,12,14 9.6,2,1 6,537,9,+++++,+++,207,3,161,7,+++++,+++,188,4 FINAL NOTES, THOUGHTS, AND QUESTIONS I've noticed that over sync NFS, initiating a file copy from my older Athlon 1.4GHz system to the RAID array system is *much, much, much* (seconds as opposed to many minutes)slower than if I initiate the copy in the same direction but from the array system. Why is this? I almost went with the SATA (8506) version of the 3Ware cards and a bunch of PATA-SATA adapters in order to maintain compatibility with future drives, likely to be SATA only. However, a colleague pointed out the foolishness of paying $200 extra ($120 for eight adapters plus $80 for the extra cost of the SATA cards) in order to (possibly) futureproof a $480 investment. I was concerned that the drives (and the PATA cables) would cause horrible heat and noise issues. These, surprisingly, didn't occur; according to 'sensors', internal temperatures only rose by a few degrees, and the server is just as (very) noisy now as pre-RAID drives. I think I'l be able to get away with stuffing the array inside my hall closet after all. The server, before I put the cards and RAID drives into the system but with the distributed-computing projects putting the CPU at 100% utilization, took the power output on my Best Fortress 750VA/450W UPS from about 55% to about 76%. With the RAID up and running and again with 100% CPU utilization, output is 87-101% with the median at perhaps 93%. I realize I really ought to invest in another UPS, but with these figures I'm tempted to get by on what I currently have. Yes, I could've saved a considerable amount of money had I gone with, say, a used dual PIII server system with regular PCI slots (and, thus, $80 Highpoint RAID cards, again for the four PATA channels and not for their RAID functionality per se) and 512MB. And I suspect that for a home user like me performance wouldn't have been too much less. But I like to buy and build systems I can use for years and years without having to bother with upgrading, and figure I've made a long-term (at least 4-5 years, which is long term in the computer world) investment that provides me with much more than just storage functionality. And again, $1.46/GB is hard to beat. -- Read my Deep Thoughts @ URL:http://www.ylee.org/blog/ PERTH ---- * Cpu(s): 6.7% us, 3.7% sy, 0.4% ni, 75.4% id, 12.3% wa, 1.4% hi, 0.0% si Mem: 515800k total, 511628k used, 4172k free, 5812k buffers Swap: 2101032k total, 13152k used, 2087880k free, 163928k cache |
dg wrote:
What kind of cables did 3ware provide, regular flat ribbon or round cables? Flat. The only thing special about them was that they lacked slave connectors. I'm glad they're flat; despite the (lack of) air flow, at some point I intend to try the fabled PATA cable origami methods I've heard about. While everything is still fresh in your mind, make sure you label the drives so you are absolutely sure which drive is which. This does concern me. How the heck do I tell them apart, even now? How di I figure out which drive is sda, which is sdb, which is sdc, etc., etc.? Advice is appreciated. For me, choosing between 2 hardware arrays or 1 software array would have been a big decision, the decision of all decisions. Not me; all my research told me that software was the way to go for both performance and downward-compatibility reasons. Great project by the way. Thank you. It's still amazes me to see that little '2.6T' label appear in the 'df -h' output. -- Read my Deep Thoughts @ URL:http://www.ylee.org/blog/ PERTH ---- * Cpu(s): 6.7% us, 3.6% sy, 0.4% ni, 75.7% id, 12.1% wa, 1.4% hi, 0.0% si Mem: 515800k total, 511540k used, 4260k free, 6088k buffers Swap: 2101032k total, 13096k used, 2087936k free, 161880k cached |
Wow,Congrats for your sucessfull build!
I am on the Way to build a storage Array myself.Thinking of an 1U-Server with 3 x SoftwareRaid5 250Gig Disks and Fedora too. Although it might be enought for now,i had the chance to expand it in the future and save some money yet. |
Yeechang Lee writes:
dg wrote: While everything is still fresh in your mind, make sure you label the drives so you are absolutely sure which drive is which. This does concern me. How the heck do I tell them apart, even now? How di I figure out which drive is sda, which is sdb, which is sdc, etc., etc.? Advice is appreciated. One way is to disconnect them one by one, and see which drive is missing in the list (unless you want to test the md driver's reconstruction abilities, you should be doing this with a kernel that does not have an md driver, probably booting from CD). You can also use that method when a drive fails (but then its even more important that the kernel does not have an md driver). Another way is to just look which ports on the cards connect with which drives. They are typically marked on the card and/or in the manual with IDE0, IDE1, etc. You also have to find out which card is which. There may be a method to do this through the PCI IDs, but I would go for the disconnection method for that. Followups set to comp.os.linux.hardware (because I read that, csiphs would probably be more appropriate). - anton -- M. Anton Ertl Some things have to be seen to be believed Most things have to be believed to be seen http://www.complang.tuwien.ac.at/anton/home.html |
I am on the Way to build a storage Array myself.Thinking of an
1U-Server with 3 x SoftwareRaid5 250Gig Disks and Fedora too. Although it might be enought for now,i had the chance to expand it in the future and save some money yet. Watch cooling: o Try to go for a case with 40x20mm fans over 40x10mm fans ---- ideal would be 40x28mm, but they tend to be noisy - 40-46dB(A) o Ideally consider 2U if not space (price) constrained re Coloco ---- easier to cool - 80mm fans over 40mm Watch PSU: o To the original poster & any multi-GB system, PSU matters ---- not just re s/w failure, but h/w failure ---- very rare, but this IS an area where over-capacity is an idea o If going for 1U, consider 350-460W over 300W ---- yes, a good 300W will be fine ---- however the higher rated ones have better cooling (twin fans) The ideal 1U PSU is one with 2x 40mm exhaust fans at one end, with the IEC connector between them. Quite rare. At the minimum get one with inlet & exhaust 40mm fan - good redundancy :-) For multi-GB, Linux with a Journalling Filesystem is important. Still not figured out how long a fsck on 2.8TB would take :-) -- Dorothy Bradbury www.dorothybradbury.co.uk for quiet Panaflo fans |
Dorothy Bradbury wrote:
Watch PSU: o To the original poster & any multi-GB system, PSU matters ---- not just re s/w failure, but h/w failure ---- very rare, but this IS an area where over-capacity is an idea PSU concerns are why I went with an Antec 550W supply as opposed to some 300-400W noname brand. Since my rackmount case does not have room for a redundant supply, I suspect this is the best I can do. As you say, PSU problems are relatively rare. That said, anyone know how I can dynamically measure the actual wattage used by my system, beyond just adding up each individual component's wattage? -- Read my Deep Thoughts @ URL:http://www.ylee.org/blog/ PERTH ---- * Cpu(s): 6.9% us, 3.5% sy, 0.8% ni, 75.8% id, 11.7% wa, 1.3% hi, 0.0% si Mem: 515800k total, 399300k used, 116500k free, 3980k buffers Swap: 2101032k total, 13360k used, 2087672k free, 47212k cached |
In article ,
Yeechang Lee wrote: Dorothy Bradbury wrote: Watch PSU: o To the original poster & any multi-GB system, PSU matters ---- not just re s/w failure, but h/w failure ---- very rare, but this IS an area where over-capacity is an idea PSU concerns are why I went with an Antec 550W supply as opposed to some 300-400W noname brand. Since my rackmount case does not have room for a redundant supply, I suspect this is the best I can do. As you say, PSU problems are relatively rare. That said, anyone know how I can dynamically measure the actual wattage used by my system, beyond just adding up each individual component's wattage? -- Read my Deep Thoughts @ URL:http://www.ylee.org/blog/ PERTH ---- * Cpu(s): 6.9% us, 3.5% sy, 0.8% ni, 75.8% id, 11.7% wa, 1.3% hi, 0.0% si Mem: 515800k total, 399300k used, 116500k free, 3980k buffers Swap: 2101032k total, 13360k used, 2087672k free, 47212k cached http://www.ahernstore.com/p4400.html about $30. I've got one. -- a d y k e s @ p a n i x . c o m Don't blame me. I voted for Gore. |
Dorothy Bradbury wrote: -Fans and Noise from them I could live with it.I will place it somewhere,where the Noise doesnt matter and the Output will be redirected with VNCServer to my Workstations. -Power Supply within 1U Servers If i choose 8 Disks,i surely will get a 550Watt Power Supply.But with 3-4 Disks,i could live with the stock PS.After a Year i will upgrade it,because it could be failing (saw some very nice Offers for used 1U-Servers). |
I need to stay away from this thread for a while, I am starting to feel some
inspiration. It has been some time since I have run Linux, and well, to be honest I have always had an urge to build a functional linux box for myself. And raid fascinates me, so, well, I need to stop reading this stuff. I can't afford a new toy now. --Dan "Yeechang Lee" wrote in message ... Great project by the way. Thank you. It's still amazes me to see that little '2.6T' label appear in the 'df -h' output. |
"Yeechang Lee" wrote in message
... CONTROLLER CARDS Initial: Two Highpoint RocketRAID 454 cards. Actual: Two 3Ware 7506-4LP cards. Why: I needed PATA cards to go with my PATA drives, and also wanted to put the two PCI-X slots on my motherboard to use. I found exactly two PATA PCI-X controller cards: The 3Ware, and the Acard AEC-6897. Given that the Acard's Linux driver compatibility looked really, really iffy, I went with the 3Ware. I briefly considered the 7506-8 model, which would've saved me about $120, but figured I'd be better off distributing the bandwidth over two PCI-X slots rather than one. No, one PCI-X card would be just as good. You don't mention the ethernet card, which could also be PCI-X. SOFTWARE Initial: Linux software RAID 5 and XFS or JFS. Actual: Linux software RAID 5 and JFS. Why: Initially I planned on software RAID knowing that the Highpoint (and the equivalent Promise and Adaptec cards) didn't do true hardware RAID. Even after switching over to 3Ware (which *does* do true hardware RAID), everything I saw and read convinced me that software RAID was still the way to go for performance, long-term compatibility, and even 400GB extra space (given I'd be building one large RAID 5 array instead of two smaller ones). Is there a comparison of Linux RAID 5 to top-end RAID cards? I suspect 3Ware is better. |
Eric Gisin wrote:
"Yeechang Lee" wrote in message ... CONTROLLER CARDS Initial: Two Highpoint RocketRAID 454 cards. Actual: Two 3Ware 7506-4LP cards. Why: I needed PATA cards to go with my PATA drives, and also wanted to put the two PCI-X slots on my motherboard to use. I found exactly two PATA PCI-X controller cards: The 3Ware, and the Acard AEC-6897. Given that the Acard's Linux driver compatibility looked really, really iffy, I went with the 3Ware. I briefly considered the 7506-8 model, which would've saved me about $120, but figured I'd be better off distributing the bandwidth over two PCI-X slots rather than one. No, one PCI-X card would be just as good. Not necessarily. PCI (and PCI-X) bandwidth is per bus, not per slot. So if those two cards are in two slots on one PCI-X bus, that's not distributing the bandwidth at all. The motherboard may offer multiple PCI-X busses, in which case the OP may want to ensure the cards are in slots that correspond to different busses. The built-in NIC on most motherboards (along with most other built-in devices) are also on one (or more) of the PCI busses, so consider bandwidth used by those as well when distributing the load. |
"Eric Gisin" wrote in message
"Yeechang Lee" wrote in message ... CONTROLLER CARDS Initial: Two Highpoint RocketRAID 454 cards. Actual: Two 3Ware 7506-4LP cards. Why: I needed PATA cards to go with my PATA drives, and also wanted to put the two PCI-X slots on my motherboard to use. I found exactly two PATA PCI-X controller cards: The 3Ware, and the Acard AEC-6897. Given that the Acard's Linux driver compatibility looked really, really iffy, I went with the 3Ware. I briefly considered the 7506-8 model, which would've saved me about $120, but figured I'd be better off distributing the bandwidth over two PCI-X slots rather than one. No, one PCI-X card would be just as good. Probably, yes. Depends on what PCI-X (version, clock) and whether the slots are seperate PCI buses or not. If seperate buses the highest clock is atainable and they both have the full PCI-X bandwidth, say 1GB/s (133MHz) or 533 MB/s (66MHz) If on same bus, the clock is lower to start with and they have to share that bus PCI-X bandwidth, say a still plenty 400MB/s each (100MHz) but may become iffy in case of 66MHz clock (266MB/s) or even 50MHz. You don't mention the ethernet card, which could also be PCI-X. What if? SOFTWARE Initial: Linux software RAID 5 and XFS or JFS. Actual: Linux software RAID 5 and JFS. Why: Initially I planned on software RAID knowing that the Highpoint (and the equivalent Promise and Adaptec cards) didn't do true hardware RAID. Even after switching over to 3Ware (which *does* do true hardware RAID), everything I saw and read convinced me that software RAID was still the way to go for performance, long-term compatibility, and even 400GB extra space (given I'd be building one large RAID 5 array instead of two smaller ones). Is there a comparison of Linux RAID 5 to top-end RAID cards? I suspect 3Ware is better. |
John-Paul Stewart wrote:
No, one PCI-X card would be just as good. Not necessarily. PCI (and PCI-X) bandwidth is per bus, not per slot. The Supermicro X5DAL-G motherboard does indeed offer a dedicated bus to each PCI-X slot, thus my desire to spread out the load with two cards. Otherwise I'd have gone with the 7506-8 eight-channel card instead and saved about $120. The built-in Gigabit Ethernet jack does indeed share one of the PCI-X slots' buses, but I only have a 100Mbit router right now. I wonder whether I should expect it to significantly contribute to overall bandwidth usage on that bus, either now or if/when I upgrade to Gigabit? -- Read my Deep Thoughts @ URL:http://www.ylee.org/blog/ PERTH ---- * Cpu(s): 5.6% us, 5.4% sy, 0.2% ni, 73.9% id, 10.4% wa, 4.6% hi, 0.0% si Mem: 515800k total, 511808k used, 3992k free, 1148k buffers Swap: 2101032k total, 240k used, 2100792k free, 345344k cached |
"Yeechang Lee" wrote in message
... The built-in Gigabit Ethernet jack does indeed share one of the PCI-X slots' buses, but I only have a 100Mbit router right now. I wonder whether I should expect it to significantly contribute to overall bandwidth usage on that bus, either now or if/when I upgrade to Gigabit? When you DO go gigabit, be sure to at least do some basic throughput benchmarks (even if its just with a stopwatch, but I suspect you will come up with a good method) and then compare afterwards. That is really good data to get firsthand from somebody with such an extreme array and well documented hardware and software setup. Really good stuff! I wonder what kind of data rates that array is capable of within the machine too. Somewhere there is a guy claiming to get 90+MB per second over gigabit ethernet using raid arrays on both ends. Gigabit switches are getting so cheap its incredible. --Dan |
Eric Gisin wrote:
Is there a comparison of Linux RAID 5 to top-end RAID cards? I suspect 3Ware is better. No, the consensus is that Linux software RAID 5 has the edge on even 3Ware (the consensus hardware RAID leader). See, among others, URL:http://www.chemistry.wustl.edu/~gelb/castle_raid.html (which does note that software striping two 3Ware hardware RAID 5 solutions "might be competitive" with software) and URL:http://staff.chess.cornell.edu/~schuller/raid.html (which states that no, all-software still has the edge in such a scenario). -- Read my Deep Thoughts @ URL:http://www.ylee.org/blog/ PERTH ---- * Cpu(s): 5.6% us, 5.6% sy, 0.3% ni, 72.2% id, 11.9% wa, 4.5% hi, 0.0% si Mem: 515800k total, 512004k used, 3796k free, 37608k buffers Swap: 2101032k total, 240k used, 2100792k free, 293748k cached |
In article ,
Yeechang Lee wrote: Eric Gisin wrote: Is there a comparison of Linux RAID 5 to top-end RAID cards? I suspect 3Ware is better. No, the consensus is that Linux software RAID 5 has the edge on even 3Ware (the consensus hardware RAID leader). See, among others, If all you care about is "rod length check" long-sequential-read or long-sequential-write performance, that's probably true. If, of course, you restrict yourself to a single stream... ....of course, in the real world, people actually do short writes and multi-stream large access every once in a while. Software RAID is particularly bad at the former because it can't safely gather writes without NVRAM. Of course, both software implementations *and* typical cheap PCI RAID card (e.g. 3ware 7/8xxx) implementations are pretty awful at the latter, too, and for no good reason that I could ever see. -- Thor Lancelot Simon "The inconsistency is startling, though admittedly, if consistency is to be abandoned or transcended, there is no problem." - Noam Chomsky |
No, one PCI-X card would be just as good.
Not necessarily. PCI (and PCI-X) bandwidth is per bus, not per slot. The Supermicro X5DAL-G motherboard does indeed offer a dedicated bus to each PCI-X slot, thus my desire to spread out the load with two cards. Otherwise I'd have gone with the 7506-8 eight-channel card instead and saved about $120. The built-in Gigabit Ethernet jack does indeed share one of the PCI-X slots' buses, but I only have a 100Mbit router right now. I wonder whether I should expect it to significantly contribute to overall bandwidth usage on that bus, either now or if/when I upgrade to Gigabit? The numbers that you posted from Bonnie++ , if I followed them correctly, showed max throughputs in the 20 MB/second range. That seems awfully slow for this sort of setup. As a comparison, I have two machines with software RAID 5 arrays, one a 2x866 P3 system with 5x120-gig drives, the other an A64 system with 8x300 gig drives, and both of them can read and write to/from their RAID 5 array at 45+ MB/s, even with the controller cards plugged into a single 32/33 PCI bus. To answer your question, GigE at full speed is a bit more than 100 MB/sec. The PCI-X busses on that motherboard are both capable of at least 100 MHz operation, which at 64 bits would give you a max *realistic* throughput of about 500 MB/second, so any performance detriment from using the gigE would likely be completely insignificant. I've got another machine with a 3Ware 7000-series card with a bunch of 120-gig drives on it (I haven't looked at the machine in quite a while), and I was pretty disappointed with the performance from that controller. It works for the intended usage (point-in-time snapshots), but responsiveness of the machine under disk I/O is pathetic - even with dual Xeons. steve |
Steve Wolfe wrote:
The numbers that you posted from Bonnie++ , if I followed them correctly, showed max throughputs in the 20 MB/second range. That seems awfully slow for this sort of setup. Agreed. However, those benchmarks were done with no tuning whatsoever (and, as noted, the three distributed computing projects going full blast); since then I've done some minor tweaking, notably the noatime mount option, which has helped. I'd post newer benchmarks but the array's right now rebuilding itself due to a kernel panic I caused by trying to use smartctl to talk to the bare drives without invoking the special 3ware switch. To answer your question, GigE at full speed is a bit more than 100 MB/sec. The PCI-X busses on that motherboard are both capable of at least 100 MHz operation, which at 64 bits would give you a max *realistic* throughput of about 500 MB/second, so any performance detriment from using the gigE would likely be completely insignificant. That was my sense as well; I suspect network saturation-by-disk will only cease to be an issue when we all hit the 10GigE world. (Actually, the 7506 cards are 66MHz PCI-X, so they don't take full advantage of the theoretical bandwidth available on the slots, anyway.) I've got another machine with a 3Ware 7000-series card with a bunch of 120-gig drives on it (I haven't looked at the machine in quite a while), and I was pretty disappointed with the performance from that controller. Appreciate the report. Fortunately, as a home user performance (or given that I'm only recording TV episodes, even data integrity actually; thus no backup plans for the array, even if backing up 2.8TB was practical in any way budgetwise) isn't my prime consideration. Were I after that, I'd probably have gone with the 9000-series controllers and SATA drives, but my wallet's busted enough with what I already have! -- Read my Deep Thoughts @ URL:http://www.ylee.org/blog/ PERTH ---- * Cpu(s): 4.7% us, 3.2% sy, 0.3% ni, 75.7% id, 14.0% wa, 2.0% hi, 0.0% si Mem: 515800k total, 510704k used, 5096k free, 18540k buffers Swap: 2101032k total, 240k used, 2100792k free, 305484k cached |
Steve Wolfe wrote:
The numbers that you posted from Bonnie++ , if I followed them correctly, showed max throughputs in the 20 MB/second range. That seems awfully slow for this sort of setup. I noticed that, too, but then noticed that the OP seemed to be running three copies of Bonnie++ in parallel. His command line was: 'bonnie++ -s 4G -m 3ware-swraid5-type -p 3 ; \ bonnie++ -s 4G -m 3ware-swraid5-type-c1 -y & \ bonnie++ -s 4G -m 3ware-swraid5-type-c2 -y & \ bonnie++ -s 4G -m 3ware-swraid5-type-c3 -y &' I'm no expert, but if he's running three in parallel on the same software RAID, I'd suspect that the total performance should be taken as the *sum* of those three---or over 60 MB/sec. As a comparison, I have two machines with software RAID 5 arrays, one a 2x866 P3 system with 5x120-gig drives, the other an A64 system with 8x300 gig drives, and both of them can read and write to/from their RAID 5 array at 45+ MB/s, even with the controller cards plugged into a single 32/33 PCI bus. As another point of comparison: 5x73GB SCSI drives, software RAID-5, one U160 SCSI channel, 32-bit/33-MHz bus, dual 1GHz P-III: writes at 36 MB/sec and read reads at 74 MB/sec. |
(Actually, the 7506 cards are 66MHz PCI-X, so they don't take full
advantage of the theoretical bandwidth available on the slots, anyway.) There is no 66MHz PCI-X. 3Ware 7506 cards are PCI 2.2 compliant 64-bit/66MHz bus master. |
"Peter" wrote in message
(Actually, the 7506 cards are 66MHz PCI-X, so they don't take full advantage of the theoretical bandwidth available on the slots, anyway.) There is no 66MHz PCI-X. The PCI-SIG seem to think different. Perhaps you know better then? And contrary to what you say elsewhere, they say there is no 100MHz spec. That was added by the industry. 3Ware 7506 cards are PCI 2.2 compliant 64-bit/66MHz bus master. |
I wrote earlier:
While everything is still fresh in your mind, make sure you label the drives so you are absolutely sure which drive is which. This does concern me. How the heck do I tell them apart, even now? How di I figure out which drive is sda, which is sdb, which is sdc, etc., etc.? As it turns out, it proved straightforward to use either 'smartctl -a --device=3ware,[0-3] /dev/twe[0-1]' or 3Ware's 3dm2 and tw_cli (available on the Web site) tools to read the serial numbers of the drives. So mystery solved. -- Read my Deep Thoughts @ URL:http://www.ylee.org/blog/ PERTH ---- * Cpu(s): 6.9% us, 3.2% sy, 2.7% ni, 77.6% id, 8.3% wa, 1.3% hi, 0.0% si Mem: 515800k total, 511768k used, 4032k free, 10648k buffers Swap: 2101032k total, 240k used, 2100792k free, 263108k cached |
Peter wrote:
There is no 66MHz PCI-X. 3Ware 7506 cards are PCI 2.2 compliant 64-bit/66MHz bus master. What's the difference? I thought 64-bit/66Mhz PCI *was* PCI-X. -- Read my Deep Thoughts @ URL:http://www.ylee.org/blog/ PERTH ---- * Cpu(s): 6.9% us, 3.2% sy, 2.7% ni, 77.6% id, 8.3% wa, 1.3% hi, 0.0% si Mem: 515800k total, 511048k used, 4752k free, 11788k buffers Swap: 2101032k total, 240k used, 2100792k free, 261024k cached |
"Al Dykes" wrote in message ... In article , Yeechang Lee wrote: Dorothy Bradbury wrote: Watch PSU: o To the original poster & any multi-GB system, PSU matters ---- not just re s/w failure, but h/w failure ---- very rare, but this IS an area where over-capacity is an idea PSU concerns are why I went with an Antec 550W supply as opposed to some 300-400W noname brand. Since my rackmount case does not have room for a redundant supply, I suspect this is the best I can do. As you say, PSU problems are relatively rare. That said, anyone know how I can dynamically measure the actual wattage used by my system, beyond just adding up each individual component's wattage? http://www.ahernstore.com/p4400.html about $30. I've got one. Thats measuring the power INTO the power supply, not what its supplying so isnt very useful for checking how close you are getting to the PSU rating. |
"Rod Speed" wrote in message
... Thats measuring the power INTO the power supply, not what its supplying so isnt very useful for checking how close you are getting to the PSU rating. Its just a matter of time before all power supplies have some sort of load monitoring method, just like most all motherboards now have software for monitoring fan speeds, temperature, voltage from the PS. Has anybody seen a smart power supply that can indicate load? --Dan |
I noticed that, too, but then noticed that the OP seemed to be running
three copies of Bonnie++ in parallel. His command line was: 'bonnie++ -s 4G -m 3ware-swraid5-type -p 3 ; \ bonnie++ -s 4G -m 3ware-swraid5-type-c1 -y & \ bonnie++ -s 4G -m 3ware-swraid5-type-c2 -y & \ bonnie++ -s 4G -m 3ware-swraid5-type-c3 -y &' I'm no expert, but if he's running three in parallel on the same software RAID, I'd suspect that the total performance should be taken as the *sum* of those three---or over 60 MB/sec. Good point- I missed that! steve |
"Yeechang Lee" wrote in message
... Peter wrote: There is no 66MHz PCI-X. 3Ware 7506 cards are PCI 2.2 compliant 64-bit/66MHz bus master. What's the difference? I thought 64-bit/66Mhz PCI *was* PCI-X. Both standards have that combo, but PCI-X is 10-30% faster. PCI-X 1.0 is 66/100/133 Mhz, 32/64 bits. |
"dg" writes:
"Rod Speed" wrote in message ... Thats measuring the power INTO the power supply, not what its supplying so isnt very useful for checking how close you are getting to the PSU rating. Sure, but it certainly gives an upper limit for the output of the PSU. So since my PSU never draws more than 180W on my Athlon 64 box, I know that my 365W power supply is overdimensioned. Of course one also has to take the load for the different voltages into consideration, not just the overall rating, and the input wattage does not help that much there. PSU efficiency for typical loads seems to be around 70%-75% (give or take a few percent depending on the quality of the PSU). Its just a matter of time before all power supplies have some sort of load monitoring method, just like most all motherboards now have software for monitoring fan speeds, temperature, voltage from the PS. Has anybody seen a smart power supply that can indicate load? That would be a bad move on the part of the PSU manufacturers: It would cost them money to include this feature, and it would convince their customers to get smaller (cheaper) PSUs next time. Followups set to colh, because I read that. - anton -- M. Anton Ertl Some things have to be seen to be believed Most things have to be believed to be seen http://www.complang.tuwien.ac.at/anton/home.html |
"Anton Ertl" wrote in message
"dg" writes: "Rod Speed" wrote in message ... Thats measuring the power INTO the power supply, not what its supplying so isnt very useful for checking how close you are getting to the PSU rating. Sure, but it certainly gives an upper limit for the output of the PSU. So since my PSU never draws more than 180W on my Athlon 64 box, I know that my 365W power supply is overdimensioned. Of course one also has to take the load for the different voltages into consideration, not just the overall rating, and the input wattage does not help that much there. PSU efficiency for typical loads seems to be around 70%-75% (give or take a few percent depending on the quality of the PSU). Its just a matter of time before all power supplies have some sort of load monitoring method, just like most all motherboards now have software for monitoring fan speeds, temperature, voltage from the PS. Has anybody seen a smart power supply that can indicate load? That would be a bad move on the part of the PSU manufacturers: It would cost them money to include this feature, and it would convince their customers to get smaller (cheaper) PSUs next time. Followups set to colh, because I read that. Right, and to hell with everyone else, who doesn't. Stupid troll. - anton |
Anton Ertl wrote in message .. . dg writes Rod Speed wrote Thats measuring the power INTO the power supply, not what its supplying so isnt very useful for checking how close you are getting to the PSU rating. Sure, but it certainly gives an upper limit for the output of the PSU. So since my PSU never draws more than 180W on my Athlon 64 box, I know that my 365W power supply is overdimensioned. In that particular situation you know that anyway from a calculation. Of course one also has to take the load for the different voltages into consideration, not just the overall rating, and the input wattage does not help that much there. Which is what I originally said. PSU efficiency for typical loads seems to be around 70%-75% (give or take a few percent depending on the quality of the PSU). Utterly mangled all over again. Its just a matter of time before all power supplies have some sort of load monitoring method, just like most all motherboards now have software for monitoring fan speeds, temperature, voltage from the PS. Has anybody seen a smart power supply that can indicate load? That would be a bad move on the part of the PSU manufacturers: Wrong. Some would buy a supply like that. It would cost them money to include this feature, and it would convince their customers to get smaller (cheaper) PSUs next time. You dont know that either. Followups set to colh, because I read that. **** that. You have always been, and always will be, completely and utterly irrelevant. |
All times are GMT +1. The time now is 02:12 AM. |
Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
HardwareBanter.com