Verbatim usb3.0 flash drive has "sinusoidal" writes

[spectatorx]

Recently i did purchase thumb drive which is verbatim 64GB pinstripe (sku: 49318) and instantly i decided to give it some basic test like copying files onto it and i noticed very weird behavior, at least something i've never seen with any other usb drives before: transfer speeds on copying files to the drive fluctuate all the time between two exact values, 18 and 26MB/s. Write graph looks sinusoidal as you can see on attached screenshot.

I do not expect it to be the fastest drive in the world as i am aware what i did purchase which is one of the cheapest but ok 64GB usb 3.0 drives. I'm just wondering what may be causing such oddities with write speeds/write process. I'm curious with what ideas you can come up.

Also i did attach to this post screenshots from crystaldisk done on this drive and other older usb3.0 drive from company named "Goodram" and my ancient usb 2.0 ocz rally 2 drive, just for comparison. All these were done with these drives connected to exactly the same port and this port is 100% sure usb 3.0, one after another, all drives formatted to exfat (filesystem doesn't matter much anyway). I do not see any firmware updates on verbatim's website. By the way i'm under impression this goodram drive behaves like usb2.0 drive, not 3.0, despite having blue color port, correct me if i am wrong on that.

Later i'm definitely going to check the drive after full format and under linux as well to see if these fluctuations are operating system independent.

 

[TheLostSwede]

All your drives are really quite slow, none of them come closer to breaking USB 2.0 write speeds.
Obviously the two USB 3.0 are faster than USB 2.0 for sequential reads.
Personally I tend to stick to SanDisk/WD for flash storage, be it USB drives or memory cards (although, also SSDs as of lately) as I've had a good experience with their products.
Never seen anything like this though, it almost looks like there's something "blocking" the write speed. Have you tried on a different computer?

Also, maybe try https://www.hdtune.com/
As it graphs the tests nicely.

 

[Mussels]

most USB drives are simply slow, i went with a portable SSD this time around after finding issues with every single USB flash drive i tested - small/no cache often causes decent reads, but slow or fluctuating writes

 

[spectatorx]

I know write speeds are not fast and that's not my question, my question is has anyone ever seen such speeds graph while writing files to the drive and anyone has any idea why is that like this?

 

[Vario]

I know write speeds are not fast and that's not my question, my question is has anyone ever seen such speeds graph while writing files to the drive and anyone has any idea why is that like this?

Heat?

 

[Steevo]

I know write speeds are not fast and that's not my question, my question is has anyone ever seen such speeds graph while writing files to the drive and anyone has any idea why is that like this?

Memory density, when the controller can write/read to two memory chips at once it almost doubles the speed.

I see this a lot writing small blocks of data to USB for flash programming controllers at work.

 

[spectatorx]

All your drives are really quite slow, none of them come closer to breaking USB 2.0 write speeds.
Obviously the two USB 3.0 are faster than USB 2.0 for sequential reads.
Personally I tend to stick to SanDisk/WD for flash storage, be it USB drives or memory cards (although, also SSDs as of lately) as I've had a good experience with their products.
Never seen anything like this though, it almost looks like there's something "blocking" the write speed. Have you tried on a different computer?

Also, maybe try https://www.hdtune.com/
As it graphs the tests nicely.

I just tried on a laptop with usb 3.0 ports and here this drive behaves in similar way but at lower rates: values are jumping between 11 and 18MB/s.
Here is a short video of copying 50GB iso file to this drive:

 

[TheLostSwede]

I just tried on a laptop with usb 3.0 ports and here this drive behaves in similar way but at lower rates: values are jumping between 11 and 18MB/s.
Here is a short video of copying 50GB iso file to this drive:

I've tested quite a few drivers over the years, especially as I used to test and review hardware for a living for many years.
I can honestly say I've never seen any drive, regardless of interface, behave like that.
I would take it back to where you bought it from, as that's not normal at all.
The other odd thing is that your random write speeds are actually not that bad.
As I said, it's as if there's something blocking the drive from going any faster. It's obviously not the system, as you've tried it on two different systems.
Bad firmware or intentional firmware limitation is the only thing I can think of.

Just to show you the performance I get from my now rather old SanDisk Extreme 64GB drive.
It's really worth spending a bit extra on these kind of things.

 

[spectatorx]

...

I got it from amazon.de, sold as brand new directly by amazon, not marketplace seller. This purchase was just to use free 10 euros which amazon was giving away during recent prime sale so that's one of reasons i do not complain about speeds of drive as i am aware what i did buy and i do not expect high speeds from it, just what is weird is the behavior you pointed out as well.

Probably i will also contact verbatim's support to ask them for explanation of that.

 

[shovenose]

I've noticed the same exact thing occasionally with certain flash drives. No idea why they do that but it's not a problem.

 

[newtekie1]

I've seen it before. I always assumed it was the tiny cache filling, the flushing, then filling again over and over.

 

[TheLostSwede]

Hmmmm, I've never come across it as I said and I used to get a bunch of free drives with press releases and what not on them. Even the cheapest turd drivers I've had, have never behaved like that and it doesn't look normal at all.
If that's a tiny cache, then it's the most useless cache ever.

I guess for free, it's not terrible though...