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Wols Lists wrote: |
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> On 16/06/20 10:04, Dale wrote: |
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>> I might add, I don't have LVM on that drive. I read it does not work |
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>> well with LVM, RAID etc as you say. Most likely, that drive will always |
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>> be a external drive for backups or something. If it ever finds itself |
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>> on the OS or /home, it'll be a last resort. |
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> LVM it's probably fine with. Raid, MUCH less so. What you need to make |
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> sure does NOT happen is a lot of random writes. That might make deleting |
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> an lvm snapshot slightly painful ... |
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> |
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> But adding a SMR drive to an existing ZFS raid is a guarantee for pain. |
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> I don't know why, but "resilvering" causes a lot of random writes. I |
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> don't think md-raid behaves this way. |
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> |
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> But it's the very nature of raid that, as soon as something goes wrong |
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> and a drive needs replacing, everything is going to get hammered. And |
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> SMR drives don't take kindly to being hammered ... :-) |
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> |
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> Even in normal use, a SMR drive is going to cause grief if it's not |
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> handled carefully. |
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> |
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> Cheers, |
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> Wol |
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|
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From what I've read, I agree. Basically, as some have posted in |
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different places, SMR drives are good when writing once and leaving it |
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alone. Basically, about like a DVD-R. From what I've read, let's say I |
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moved a lot of videos around, maybe moved the directory structure |
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around, which means a lot of data to move. I think I'd risk just |
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putting a new file system on it and then backup everything from |
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scratch. It may take a little longer given the amount of data but it |
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would be easier on the drive. It would keep it from hammering as you |
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put it that drive to death. |
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I've also read about the resilvering problems too. I think LVM |
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snapshots and something about BTFS(sp?) has problems. I've also read |
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that on windoze, it can cause a system to freeze while it is trying to |
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rewrite the moved data too. It gets so slow, it actually makes the OS |
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not respond. I suspect it could happen on Linux to if the conditions |
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are right. |
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I guess this is about saving money for the drive makers. The part that |
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seems to really get under peoples skin tho, them putting those drives |
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out there without telling people that they made changes that affect |
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performance. It's bad enough for people who use them where they work |
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well but the people that use RAID and such, it seems to bring them to |
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their knees at times. I can't count the number of times I've read that |
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people support a class action lawsuit over shipping SMR without telling |
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anyone. It could happen and I'm not sure it shouldn't. People using |
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RAID and such, especially in some systems, they need performance not |
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drives that beat themselves to death. |
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|
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My plan, avoid SMR if at all possible. Right now, I just don't need the |
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headaches. The one I got, I'm lucky it works OK, even if it does bump |
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around for quite a while after backups are done. |
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My new to me hard drive is still testing. Got a few more hours left |
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yet. Then I'll run some more tests. It seems to be OK tho. |
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|
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Dale |
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|
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:-) :-) |
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