Question raid 0 speed issue

May 15, 2022
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hello, i have two 3tb disks in raid 0 (so win sees it as 6gb disk), its seagate 7200rpm with 200mb/s read/writes and wd 5200rpm with 150mb/s read/writes, what i understand the raid 0 should have read/write speeds of the two disks combined so in my case 350mb/s, but im getting the speeds only of that slower wd disk 150mb/s, anyone know why and how to fix it? i tested it by copying big files from and to my nvme 6000mb/s (all the speeds are confirmed by crystaldiskmark benchmark ), thank you
 
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USAFRet

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Performance of a RAID 0 depends on the speed of the slowest device.
Thats the way it is, these is no "fix".

In theory, and absolute perfect conditions, you get (almost) 2x the speed of the slowest.
Here, that would be 300mbps.

How is this RAID 0 configured?
Why the RAID 0?
 
May 15, 2022
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How is this RAID 0 configured?
Why the RAID 0?
it was configured in win 10 in disk management if i recall correctly, it was months ago i just didnt test it till now, i picked raid 0 for the double speed i read about, i have it mirrored to my external 8tb disk so i dont lose data if the raid brakes down (btw 3gb in my first post is a typo its 3tb lol)
also first i tried to configure it in bios, but after setting the raid 0 my nvme wasnt bootable, system didnt even see it

What are model names of your drives?
Seagate Barracudas are all SMR. They have terrible write performance consistency.
Seagate Barracuda ST3000DM008
WD Red Plus WD30EFRX
 
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May 15, 2022
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Mirrored to the 8TB how, exactly?

What is this RAID 0 used for? What data is on it?
In consumer use, RAID is rarely a good idea.
Seagate BackUp Plus Hub 8 TB came with an application called toolkit that can sync/mirror, i have all kinds of stuff on it, movies, games, music etc
 

USAFRet

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Seagate BackUp Plus Hub 8 TB came with an application called toolkit that can sync/mirror, i have all kinds of stuff on it, movies, games, music etc
If this is an actual "mirror" (mostly a RAID 1?), then your slow speed may be that of the 8TB and its connection.

And for your stated use, that RAID 0 is totally not needed, even if you had good drives to do it with.
That SMR Seagate is not useful for this.
 
May 15, 2022
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If this is an actual "mirror" (mostly a RAID 1?), then your slow speed may be that of the 8TB and its connection.
as i said in original post the 150mb/s speed is between raid0 of those two 3tb disks and my main nvme disk, not the 8tb ext disk (this one is not in any raid, i just launch the syncing app from time to time to have the latest backup of that raid0 datas), so you guys think that 150mb/s writes and reads is normal for this raid of mine?
 
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May 15, 2022
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In addition, there comes CPU overhead, and if the hdd are indeed SMR, then I'd agree to the other comments, RAID configuration are complete useless on this system.
i dont see a disadvantage though, speeds are same as if those disks were separated to d:/ and e:/ drives, but big advantage for me is that i can have same type of data in one folder, instead of two folders on two drives when i cant sort the files by name/date etc (i have 4tb of same type of data files so in old way i couldnt have it in one folder)
 
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USAFRet

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Disadvantages:
Complexity, possibility of fail, expectation of 'speed' when there is none. No real backup (no, your 'mirror' is not a backup).

The only advantage you get is one drive letter instead of two.
 
May 15, 2022
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Disadvantages:
Complexity, possibility of fail, expectation of 'speed' when there is none. No real backup (no, your 'mirror' is not a backup).

The only advantage you get is one drive letter instead of two.
it really is a backup, even if the function is called "mirror", i have the same files of the same size on both, mirroring in this case means that if i delete something from raid and then launch the application it will sync and delete the same file from external disk and if i copy something from my nvme to raid then the app will copy the same file from raid to the external disk, which i can take with me to work for example, see the pic D:/ is raid0 and E:/ is external disk
 
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USAFRet

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it really is a backup, even if the function is called "mirror", i have the same files of the same size on both, mirroring in this case means that if i delete something from raid and then launch the application it will sync and delete the same file from external disk and if i copy something from my nvme to raid then the app will copy the same file to the external disk, which i can take with me to work for example
And if you accidentally delete something?
Gone on both.

Get a nasty virus or ransomware?
Happens on both.

I don't know the inner workings of that Seagate thing, but it doesn't sound like a real backup routine.
No matter how much Seagate says it is.

General backup concept is 3-2-1.
3 copies, on at least 2 different media, at least one offsite or otherwise inaccessible.
Preferably automated.

But if it meets your needs, go for it.
Not for me.

And that RAID....absolutely not for me.
 
May 15, 2022
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And if you accidentally delete something?
Gone on both.
thats why i dont have the application running all the time, so when i accidently delete something i can manually copy it from the other before they sync after i launch the app

Have we addressed the theoretical 'speed' problem of the RAID 0?
i would like to set the raid in bios to see if theres a difference in speeds but as i said my nvme disappears from booting options after i set the raid of those two other disks
 
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May 15, 2022
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This is janky as hell. An on-demand backup of a pointless RAID 0. Best of luck to you; this is way too amateur hour for me to spend time unpacking this mess.
not pointless, as i said i cannot have one folder with files i need in it if those two disks are not in raid 0, because the folder is 4tb big and disks are 3tb big each
 
May 15, 2022
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Again, a RAID 0 depends on the speed of the slowest drive.
And smr drives are never a good option for a RAID array, of any type.
in that case i can rest my case, although im a bit confused, because when i was researching about raids many articels said that raid 0 is good bacause it combines the speeds of both disks in such a way that both disks read and write at the same time therefore the speed is doubled
 

USAFRet

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in that case i can rest my case, although im a bit confused, because when i was researching about raids many articels said that raid 0 is good bacause it combines the speeds of both disks in such a way that both disks read and write at the same time therefore the speed is doubled
Given 2 identical drives (HDD), a RAID 0 can (not will) see speeds 2x the speed of the individual drives.
Given 2 unequal drives, the speed of the slowest dictates.

You sort of get faster than a single drive, but it is not a simple as A + B.
It doesn't make the slower drive read/write as fast as the faster drive.

We've seen people here wanting to RAID 0 between an SSD and HDD, assuming that the HDD will be 'faster'.
No, quite the opposite....the whole array slows down to the performance of the HDD.

But in your use case, as with 99% of all consumer use...a RAID 0 is irrelevant and counter productive.
A 2 hour movie still takes 2 hours to watch.
Game FPS does not increase.
etc
 

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