October 7, 200916 yr Hi I'm looking to increase the size of my parity drive from 1TB to 1.5TB so I can start replacing some of my 500GB drives with 1.5TB. Would the above drive be suitable for parity, or should I be looking at a 7200rpm drive? I use a cache drive so presume write speeds shouldn't be affected (other than when data is being copied from cache to the array but I'll be asleep so don't care!). All other discs are 720rpm and the majority of data on my unraid box are Bluray rips. I'm guessing there's no real reason why I shouldn't go for it......?
October 7, 200916 yr We always recommend using the fastest drive possible for parity. Every parity operation consists of a read and write. Later on as you upgrade drives to larger spindles, you will be glad you did. Keep in mind that even small updates to a filesystem, require updates to the superblock, (Which is yet another parity operation).
October 7, 200916 yr Author We always recommend using the fastest drive possible for parity. Every parity operation consists of a read and write. Later on as you upgrade drives to larger spindles, you will be glad you did. Keep in mind that even small updates to a filesystem, require updates to the superblock, (Which is yet another parity operation). Fair enough - thanks.
October 7, 200916 yr Take a look at your other drives' speeds. Even though they're 7200rpm, they might still be a bit slower than the 5400rpm 1.5tb. I have a three platter 500GB 7200rpm WD drive that's a bit slower than one of my 5400rpm 1.5TB WD drives. I think due to the density of data, and the general speed increases in drives over the years, 5400rpms have improved greatly.
October 7, 200916 yr I've just used this same drive and capacity as parity. No problems so far, but, I really wish WD had a 1.5 TB Black edition.
October 7, 200916 yr Hi I'm looking to increase the size of my parity drive from 1TB to 1.5TB so I can start replacing some of my 500GB drives with 1.5TB. Would the above drive be suitable for parity, or should I be looking at a 7200rpm drive? I use a cache drive so presume write speeds shouldn't be affected (other than when data is being copied from cache to the array but I'll be asleep so don't care!). All other discs are 720rpm and the majority of data on my unraid box are Bluray rips. I'm guessing there's no real reason why I shouldn't go for it......? Like fitbrit I also use one of these as parity. To my shame I didn't even realise it wasn't 7200rpm when I bought it! Samsung + that capacity = sold. I like Samsung drives as they're quiet and run cool. Anyway no problems really, I get 15-18 megabytes a second writes across the network using it. That said I am looking to upgrade to a 2TB parity drive and when I do I'll go 7200rpm just to get that boost in speed and responsiveness for writes.
October 8, 200916 yr Take a look at your other drives' speeds. Even though they're 7200rpm, they might still be a bit slower than the 5400rpm 1.5tb. I have a three platter 500GB 7200rpm WD drive that's a bit slower than one of my 5400rpm 1.5TB WD drives. I think due to the density of data, and the general speed increases in drives over the years, 5400rpms have improved greatly. Higher bit density can give a 5400 RPM drive equivalent "read" performance to a 7200 RPM drive with lower bit density. Unfortunately, you cannot cheat physics, and the platter must rotate a full revolution between reading a given sector and writing to it. Therefore, when writing to the array the 5400 RPM drive is at a disadvantage, regardless of the bit density. Joe L.
October 8, 200916 yr Ah, so sequential reads on a 5400 may have improved over time due to density, but when a head still has to physically move across a disk to read the next bit, it is limited by mechanical motion. Thanks for the clarification, Joe.
October 8, 200916 yr Ah, so sequential reads on a 5400 may have improved over time due to density, but when a head still has to physically move across a disk to read the next bit, it is limited by mechanical motion. Thanks for the clarification, Joe. It is not that the head has to move...it does not...it does not need to move at all until it needs to advance to the next cylinder. Once positioned on a given cylinder to first read a sector, then it must wait for the platter to spin a full revolution and the same sector to appear under the head once more to write the new contents. That "wait" time is fixed by the rotational speed of the platter, no matter how tightly packed the bits are on a given cylinder. The buffering of the disk helps some, as it might be able to read a great part of a cylinder on a single rotation, and then after "writing" a sector it might not need to wait for a full rotation to read the next sector on a cylinder. It will still have to wait part of a rotation to write the subsequent sector. The tight packing of bits on a cylinder may hurt some, if the built in buffer is unable to hold the contents of a full cylinder. At that point, the buffer helps on sequential "reads" of the disk sectors, but does nothing helpful on "writes" Joe L.
October 8, 200916 yr I use the 1.5tb ecogreens f2 drives for my parity and data drives and I have speeds rank up there with the ones I see posted. I also use a 500gb f2 ecogreen for my cache drive and it does great too. I missed out on getting a couple more for the system last week when Fry's had em on sale. Gotta get 2-3 more to add more space.
October 8, 200916 yr I haven't read any good things about the Spinpoint line when it is used in disk arrays. In fact, in many reviews on the web this disk trails all the others in the benchmarks. So yes, it will work as parity disk, but if you can afford a few bucks more, then get something more serious, like the WD-RE4. You'll be glad you did that later. Yours, Purko
October 8, 200916 yr www.pcgameshardware.com/aid,679981/Samsung-Ecogreen-F2-HD154UI-15-Terabyte-hard-drive-reviewed/Reviews/
October 8, 200916 yr www.pcgameshardware.com/aid,679981/Samsung-Ecogreen-F2-HD154UI-15-Terabyte-hard-drive-reviewed/Reviews/ That guy didn't do any benchmarking himself. He just sucked that info out of his thimbs. Here's a review that can be a little more informational: http://www.tomshardware.com/reviews/2tb-hdd-caviar,2261-6.html
October 8, 200916 yr so the 500GB/1TB/1.5TB samsung drives are basically all you're saying? the tomshardware review doesnt seem to cover the 1.5tb drives and i thought the 1.5tb drives had been updated a bit internally compared to their 500gb/1tb predecessors
October 8, 200916 yr the 1.5tb drives had been updated a bit internally compared to their 500gb/1tb predecessors That may very well be true. As I said, go for it! Personally, I won't. But that's just me. Cheers!
October 8, 200916 yr Author Nice to see I've sparked a healthy debate. Seems like there is a large pinch of personal preference on this subject. I think I'll fall off the fence onto the 7200rpm side and start looking around. Thanks
October 8, 200916 yr Nice to see I've sparked a healthy debate. Seems like there is a large pinch of personal preference on this subject. I think I'll fall off the fence onto the 7200rpm side and start looking around. Thanks I highly recommend it at least for parity and/or possibly cache. I saw a large improvement in my systems response after my upgrade.
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