Question 2.5" HDDs slow down the more they're filled with data

swapjim

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Nov 16, 2015
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I have two 2.5" USB drives: a 2015 WD My Passport Ultra 2TB and a 2015 Seagate Backup Plus Portable 2TB.

Up until the point they're 50% full, their read and write speed is around 120MB/sec. When 70% full, their r/w speed is around 70MB/sec. And when 90% full, the r/w speed is around 50MB/sec.

I've tried defragmenting and formatting.

Why is this happening? Can I get full speed even at 90% full? Is this documented anywhere so I can read more about it?
 

Tech Junky

Diamond Member
Jan 27, 2022
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That's just how they operate. There's just not as much room to shuffle the data around which slows them down. If you want to speed things up you could use raid 0 to combine them into a single logical disk and double the controller speed. Ideally though using a larger drive would make more sense.

Do they need to be portable? What are you using them for? Internal spinners these days can hit up to 300mb/s and portables 1gb/s with an NVME. if you have TB then upwards of 3gb/s.
 

swapjim

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Nov 16, 2015
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The only way I can explain this is if they're using shingled magnetic recording. But that doesn't slow down reading, doesn't it?

I know I've got options if I want to go faster but I don't want to spend the money right now. The reason I got 2.5" drives back then is because they're quieter than 3.5" ones and 100MB/sec was acceptable.
 

mindless1

Diamond Member
Aug 11, 2001
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Heh, VL beat me by 2 minutes.

Any HDD will get slower access, the further in on the platters it places the data as it fills up. This is due to a lower linear speed. At any RPM, the inner tracks of the platter have lower linear speed than the outer.

Considering they are now pushing 8 years old (unless you stated 2015 only as the initial product release date, not when you started using them), I'd replace them soon for that reason.

Modern 3.5" externals, especially if they don't have a lot of platters in them, are pretty quiet. I have one 2-3 feet away that I can't hear unless it's doing aggressive seeking on a highly fragmented file, or a slight sound upon initial spinup.
 

Tech Junky

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Jan 27, 2022
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Another option would be using something like this - https://www.amazon.com/Sabrent-Drive-Docking-Station-DS-4SSD/dp/B0711L68MS where you can use multiple drives in a single enclosure. This would give you the ability to use a software raid in just about any OS.

There are cheaper 2-bay options though around $30 that could work as well. With them being open and just being able to drop drives into them they offer more flexibility as time goes by. The only issue with R0 is you need to make backups since if you lose a single disk you're data is gone. Since we're talking about ~4TB of data a single 3.5" drive would be a cheap option but, for the long term I would be looking at 2X the space needed as a rule of thumb for future growth.

There are docks that fit both 2.5 & 3.5 drives in the same chassis where if you got a 4 slot one you could have your R0 on 3 of the drives and pop the 3.5" backup drive in as needed for backups to go to. Considering the age of the current drives it might be best to think about this as a new solution and get the data backed up onto new disks.
 
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WilliamM2

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Jun 14, 2012
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I run 5 in a raid 10 internally in a "media PC" setting and don't hear them at all. WD Red drives running 24/7 at 5400.


I would shuck them and make them internal otherwise you would have to boot with them attached for the raid to pick them up and be accessible.

In other words, you can't.
 

mindless1

Diamond Member
Aug 11, 2001
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The (only) reason we have is "The reason I got 2.5" drives back then is because they're quieter than 3.5" ones and 100MB/sec was acceptable. "

Without further info about other needs, I'd just get a 6TB 3.5" external, immediately copy any important data onto it, and if the budget is tight, wait to get another 6TB 3.5" external. If you catch a sale, that's about $100. If you want 2.5", settle for 4TB around that price point.
 

swapjim

Member
Nov 16, 2015
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HDDs are faster at the beginning of the drive (outer tracks). They progressively get slower towards the middle.

Ah, but of course! It makes perfect sense! My initial question has been answered, thank you!

Is there a reason for having them be "portable" ?

The noise. I tested 3.5" drives back then but the noise was too much for me. I would consider them again, of course.

Also, thank you for suggesting these docks. I didn't know they existed.

Considering they are now pushing 8 years old (unless you stated 2015 only as the initial product release date, not when you started using them), I'd replace them soon for that reason.

My data is located in said two drives, along with in two 3.5" ones (a WD Red and a Seagate IronWolf) that I bought in 2020 (or 2021) and they reside inside a NAS. I work with the data on one of the 2.5" drives and sync to the NAS and the other 2.5" drive a few times per day. I don't keep the NAS always on, again because of the noise. So for every sync I boot the NAS, sync the files, and then shut it down. It's all scripted so I only press a button. The NAS automatically boots 3 times a day to take a snapshot of the data and then shuts down. Snapshots protect me from ransomware. Otherwise I wouldn't have a NAS.

The fact that I have the data is in 4 locations makes me feel safe as the worst case scenario is me losing a few hours of work. But you guys mentioning that 8 years is too old for a drive (believe it or not it didn't cross my mind) made me pause and think how much value a few hours of work has. So I would like to ask a few questions.

My setup is one primary copy of the data I work on, which I then sync to other drives a few times a day. Which of the following is more of a reliable solution to store this primary copy?

- An internal 2.5" SSD in a USB case
- An M.2 SSD in a USB case
- An external USB SSD
- An external 2.5" HDD
- An internal 3.5" HDD in USB case

I know that RAID-1 is better than all of these options, because of the rendundancy. But exclusing that, which of the previous 4 options is more reliable?
 

Tech Junky

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Jan 27, 2022
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The noise. I tested 3.5" drives back then but the noise was too much for me. I would consider them again, of course.

Also, thank you for suggesting these docks. I didn't know they existed.
Drives these days aren't as noisy as they used to be. Sure, if you get some junk drive it will be louder than a more common drive. If it makes too much noise these days it's a good idea to return it anyway as they're virtually silent compared to the olden days when Floppies were a thing.

Docks are great for flexibility.

I don't keep the NAS always on, again because of the noise.
Then I would move it somewhere not where you're in earshot of it. Kind of defeats the purpose by turning it off.

Depending on the NAS though it might have a USB port which you could plug the dock into it for backing up periodically.

I know that RAID-1 is better than all of these options
Not really. It's just a mirror copy of the primary drive and just helps if one disk fails.

I would take whatever size your internal drive is and double it for a "backup" in a portable format.
I would do the same for the NAS backup or just concentrate on backing up the NAS with a dock at least the same size as the NAS storage or switch the NAS to Raid 0 for faster performance and double the size of the backup drive to compensate. Raid 0 will also double your storage capacity.

The flip side is maybe consider a 2nd NAS as your backup of the backup. Eventually they will fail as well.

Now, if you really can't stand the noise then look into SSD fir the PC and backup. 4TB isn't too bad around $300 8TB run s about $600

 

tcsenter

Lifer
Sep 7, 2001
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Last resort: clone each disk to spare, long format (with media check) the original, then clone everything back. Don't use any forensic or bit-for-bit mode that will copy free space. This should via most cloning apps result in about the most defragmented disk volume you can get. If you are filling the last 15% capacity of any HDD you're gonna experience slow down in performance.
 
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